diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5AbstractCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5AbstractCodegen.java
index f6cacde238a..1c4aa5c6085 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5AbstractCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5AbstractCodegen.java
@@ -105,6 +105,7 @@ public class CppQt5AbstractCodegen extends AbstractCppCodegen implements Codegen
         typeMapping.put("number", "double");
         typeMapping.put("array", "QList");
         typeMapping.put("map", "QMap");
+        typeMapping.put("set", "QSet");
         typeMapping.put("object", PREFIX + "Object");
         // mapped as "file" type for OAS 3.0
         typeMapping.put("ByteArray", "QByteArray");
@@ -122,6 +123,7 @@ public class CppQt5AbstractCodegen extends AbstractCppCodegen implements Codegen
         systemIncludes.add("QString");
         systemIncludes.add("QList");
         systemIncludes.add("QMap");
+        systemIncludes.add("QSet");
         systemIncludes.add("QDate");
         systemIncludes.add("QDateTime");
         systemIncludes.add("QByteArray");
diff --git a/modules/openapi-generator/src/main/resources/cpp-qt5-client/helpers-header.mustache b/modules/openapi-generator/src/main/resources/cpp-qt5-client/helpers-header.mustache
index 0a8e6b8b214..994ae817630 100644
--- a/modules/openapi-generator/src/main/resources/cpp-qt5-client/helpers-header.mustache
+++ b/modules/openapi-generator/src/main/resources/cpp-qt5-client/helpers-header.mustache
@@ -25,21 +25,33 @@ bool setDateTimeFormat(const QString&);
 template <typename T>
 QString toStringValue(const QList<T> &val);
 
+template <typename T>
+QString toStringValue(const QSet<T> &val);
+
 template <typename T>
 bool fromStringValue(const QList<QString> &inStr, QList<T> &val);
 
+template <typename T>
+bool fromStringValue(const QSet<QString> &inStr, QList<T> &val);
+
 template <typename T>
 bool fromStringValue(const QMap<QString, QString> &inStr, QMap<QString, T> &val);
 
 template <typename T>
 QJsonValue toJsonValue(const QList<T> &val);
 
+template <typename T>
+QJsonValue toJsonValue(const QSet<T> &val);
+
 template <typename T>
 QJsonValue toJsonValue(const QMap<QString, T> &val);
 
 template <typename T>
 bool fromJsonValue(QList<T> &val, const QJsonValue &jval);
 
+template <typename T>
+bool fromJsonValue(QSet<T> &val, const QJsonValue &jval);
+
 template <typename T>
 bool fromJsonValue(QMap<QString, T> &val, const QJsonValue &jval);
 
@@ -68,6 +80,18 @@ QString toStringValue(const QList<T> &val) {
     return strArray;
 }
 
+template <typename T>
+QString toStringValue(const QSet<T> &val) {
+    QString strArray;
+    for (const auto &item : val) {
+        strArray.append(toStringValue(item) + ",");
+    }
+    if (val.count() > 0) {
+        strArray.chop(1);
+    }
+    return strArray;
+}
+
 QJsonValue toJsonValue(const QString &value);
 QJsonValue toJsonValue(const QDateTime &value);
 QJsonValue toJsonValue(const QByteArray &value);
@@ -90,6 +114,15 @@ QJsonValue toJsonValue(const QList<T> &val) {
     return jArray;
 }
 
+template <typename T>
+QJsonValue toJsonValue(const QSet<T> &val) {
+    QJsonArray jArray;
+    for (const auto &item : val) {
+        jArray.append(toJsonValue(item));
+    }
+    return jArray;
+}
+
 template <typename T>
 QJsonValue toJsonValue(const QMap<QString, T> &val) {
     QJsonObject jObject;
@@ -123,6 +156,17 @@ bool fromStringValue(const QList<QString> &inStr, QList<T> &val) {
     return ok;
 }
 
+template <typename T>
+bool fromStringValue(const QSet<QString> &inStr, QList<T> &val) {
+    bool ok = (inStr.count() > 0);
+    for (const auto &item : inStr) {
+        T itemVal;
+        ok &= fromStringValue(item, itemVal);
+        val.push_back(itemVal);
+    }
+    return ok;
+}
+
 template <typename T>
 bool fromStringValue(const QMap<QString, QString> &inStr, QMap<QString, T> &val) {
     bool ok = (inStr.count() > 0);
@@ -162,6 +206,21 @@ bool fromJsonValue(QList<T> &val, const QJsonValue &jval) {
     return ok;
 }
 
+template <typename T>
+bool fromJsonValue(QSet<T> &val, const QJsonValue &jval) {
+    bool ok = true;
+    if (jval.isArray()) {
+        for (const auto jitem : jval.toArray()) {
+            T item;
+            ok &= fromJsonValue(item, jitem);
+            val.insert(item);
+        }
+    } else {
+        ok = false;
+    }
+    return ok;
+}
+
 template <typename T>
 bool fromJsonValue(QMap<QString, T> &val, const QJsonValue &jval) {
     bool ok = true;
diff --git a/samples/client/petstore/cpp-qt5/client/PFXHelpers.h b/samples/client/petstore/cpp-qt5/client/PFXHelpers.h
index 8bed4f0e80c..a0d2c4d47a4 100644
--- a/samples/client/petstore/cpp-qt5/client/PFXHelpers.h
+++ b/samples/client/petstore/cpp-qt5/client/PFXHelpers.h
@@ -33,21 +33,33 @@ bool setDateTimeFormat(const QString&);
 template <typename T>
 QString toStringValue(const QList<T> &val);
 
+template <typename T>
+QString toStringValue(const QSet<T> &val);
+
 template <typename T>
 bool fromStringValue(const QList<QString> &inStr, QList<T> &val);
 
+template <typename T>
+bool fromStringValue(const QSet<QString> &inStr, QList<T> &val);
+
 template <typename T>
 bool fromStringValue(const QMap<QString, QString> &inStr, QMap<QString, T> &val);
 
 template <typename T>
 QJsonValue toJsonValue(const QList<T> &val);
 
+template <typename T>
+QJsonValue toJsonValue(const QSet<T> &val);
+
 template <typename T>
 QJsonValue toJsonValue(const QMap<QString, T> &val);
 
 template <typename T>
 bool fromJsonValue(QList<T> &val, const QJsonValue &jval);
 
+template <typename T>
+bool fromJsonValue(QSet<T> &val, const QJsonValue &jval);
+
 template <typename T>
 bool fromJsonValue(QMap<QString, T> &val, const QJsonValue &jval);
 
@@ -76,6 +88,18 @@ QString toStringValue(const QList<T> &val) {
     return strArray;
 }
 
+template <typename T>
+QString toStringValue(const QSet<T> &val) {
+    QString strArray;
+    for (const auto &item : val) {
+        strArray.append(toStringValue(item) + ",");
+    }
+    if (val.count() > 0) {
+        strArray.chop(1);
+    }
+    return strArray;
+}
+
 QJsonValue toJsonValue(const QString &value);
 QJsonValue toJsonValue(const QDateTime &value);
 QJsonValue toJsonValue(const QByteArray &value);
@@ -98,6 +122,15 @@ QJsonValue toJsonValue(const QList<T> &val) {
     return jArray;
 }
 
+template <typename T>
+QJsonValue toJsonValue(const QSet<T> &val) {
+    QJsonArray jArray;
+    for (const auto &item : val) {
+        jArray.append(toJsonValue(item));
+    }
+    return jArray;
+}
+
 template <typename T>
 QJsonValue toJsonValue(const QMap<QString, T> &val) {
     QJsonObject jObject;
@@ -131,6 +164,17 @@ bool fromStringValue(const QList<QString> &inStr, QList<T> &val) {
     return ok;
 }
 
+template <typename T>
+bool fromStringValue(const QSet<QString> &inStr, QList<T> &val) {
+    bool ok = (inStr.count() > 0);
+    for (const auto &item : inStr) {
+        T itemVal;
+        ok &= fromStringValue(item, itemVal);
+        val.push_back(itemVal);
+    }
+    return ok;
+}
+
 template <typename T>
 bool fromStringValue(const QMap<QString, QString> &inStr, QMap<QString, T> &val) {
     bool ok = (inStr.count() > 0);
@@ -170,6 +214,21 @@ bool fromJsonValue(QList<T> &val, const QJsonValue &jval) {
     return ok;
 }
 
+template <typename T>
+bool fromJsonValue(QSet<T> &val, const QJsonValue &jval) {
+    bool ok = true;
+    if (jval.isArray()) {
+        for (const auto jitem : jval.toArray()) {
+            T item;
+            ok &= fromJsonValue(item, jitem);
+            val.insert(item);
+        }
+    } else {
+        ok = false;
+    }
+    return ok;
+}
+
 template <typename T>
 bool fromJsonValue(QMap<QString, T> &val, const QJsonValue &jval) {
     bool ok = true;