diff --git a/modules/openapi-generator/src/main/resources/r/api.mustache b/modules/openapi-generator/src/main/resources/r/api.mustache
index 460a92365a0..9606add1c3b 100644
--- a/modules/openapi-generator/src/main/resources/r/api.mustache
+++ b/modules/openapi-generator/src/main/resources/r/api.mustache
@@ -385,15 +385,62 @@
       {{#isExplode}}
       # explore
       for (query_item in `{{{paramName}}}`) {
+        {{#items}}
+        {{#isEnum}}
+        # validate enum values
+        if (!(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+          {{#useDefaultExceptionHandling}}
+          stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
+          {{/useDefaultExceptionHandling}}
+          {{#useRlangExceptionHandling}}
+          rlang::abort(message = "Invalid value for `{{paramName}}` when calling {{classname}}${{operationId}}. Must be {{_enum}}.",
+                       .subclass = "ApiException",
+                       ApiException = ApiException$new(status = 0,
+                                                       reason = "Invalid value for `{{paramName}}` when calling {{classname}}${{operationId}}. Must be {{_enum}}."))
+          {{/useRlangExceptionHandling}}
+        }
+        {{/isEnum}}
+        {{/items}}
         query_params[["{{{baseName}}}"]] <- c(query_params[["{{{baseName}}}"]], list(`{{{baseName}}}` = query_item))
       }
       {{/isExplode}}
       {{^isExplode}}
       # no explore
+      {{#items}}
+      {{#isEnum}}
+      # validate enum values
+      for (query_item in `{{{paramName}}}`) {
+        if (!(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+          {{#useDefaultExceptionHandling}}
+          stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
+          {{/useDefaultExceptionHandling}}
+          {{#useRlangExceptionHandling}}
+          rlang::abort(message = "Invalid value for `{{paramName}}` when calling {{classname}}${{operationId}}. Must be {{_enum}}.",
+                       .subclass = "ApiException",
+                       ApiException = ApiException$new(status = 0,
+                                                       reason = "Invalid value for `{{paramName}}` when calling {{classname}}${{operationId}}. Must be {{_enum}}."))
+          {{/useRlangExceptionHandling}}
+        }
+      }
+      {{/isEnum}}
+      {{/items}}
       query_params[["{{{baseName}}}"]] <- I(paste(lapply(`{{{paramName}}}`, URLencode, reserved = TRUE), collapse = ","))
       {{/isExplode}}
       {{/isArray}}
       {{^isArray}}
+      {{#isEnum}}
+      if (!(`{{paramName}}` %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+        {{#useDefaultExceptionHandling}}
+        stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
+        {{/useDefaultExceptionHandling}}
+        {{#useRlangExceptionHandling}}
+        rlang::abort(message = "Invalid value for `{{paramName}}` when calling {{classname}}${{operationId}}. Must be {{_enum}}.",
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(status = 0,
+                                                     reason = "Invalid value for `{{paramName}}` when calling {{classname}}${{operationId}}. Must be {{_enum}}."))
+        {{/useRlangExceptionHandling}}
+      }
+      {{/isEnum}}
       query_params[["{{baseName}}"]] <- `{{paramName}}`
       {{/isArray}}
 
diff --git a/samples/client/petstore/R-httr2-wrapper/R/pet_api.R b/samples/client/petstore/R-httr2-wrapper/R/pet_api.R
index ef23b725e3d..9308019bb17 100644
--- a/samples/client/petstore/R-httr2-wrapper/R/pet_api.R
+++ b/samples/client/petstore/R-httr2-wrapper/R/pet_api.R
@@ -943,6 +943,13 @@ PetApi <- R6::R6Class(
 
       # explore
       for (query_item in `status`) {
+        # validate enum values
+        if (!(query_item %in% c("available", "pending", "sold"))) {
+          rlang::abort(message = "Invalid value for `status` when calling PetApi$find_pets_by_status. Must be [available, pending, sold].",
+                       .subclass = "ApiException",
+                       ApiException = ApiException$new(status = 0,
+                                                       reason = "Invalid value for `status` when calling PetApi$find_pets_by_status. Must be [available, pending, sold]."))
+        }
         query_params[["status"]] <- c(query_params[["status"]], list(`status` = query_item))
       }
 
diff --git a/samples/client/petstore/R-httr2-wrapper/tests/testthat/test_petstore.R b/samples/client/petstore/R-httr2-wrapper/tests/testthat/test_petstore.R
index 2fe987360bc..9758fd3fb3c 100644
--- a/samples/client/petstore/R-httr2-wrapper/tests/testthat/test_petstore.R
+++ b/samples/client/petstore/R-httr2-wrapper/tests/testthat/test_petstore.R
@@ -235,6 +235,16 @@ test_that("GetPetById with data_file", {
 })
 
 test_that("find_pets_by_status", {
+  # input invalid
+  var_status <- c("something") # array[character] | Tags to filter by
+  result <- tryCatch(pet_api$find_pets_by_status(var_status),
+                     ApiException = function(ex) ex
+  )
+
+  expect_equal(result$ApiException$reason, "Invalid value for `status` when calling PetApi$find_pets_by_status. Must be [available, pending, sold].")
+})
+
+test_that("find_pets_by_tags", {
   pet_tag_test <- Pet$new("name_test",
     photoUrls = list("photo_test", "second test"),
     category = Category$new(id = 4455, name = "test_cat"),
diff --git a/samples/client/petstore/R-httr2/R/pet_api.R b/samples/client/petstore/R-httr2/R/pet_api.R
index 891f456f355..c040ca153e7 100644
--- a/samples/client/petstore/R-httr2/R/pet_api.R
+++ b/samples/client/petstore/R-httr2/R/pet_api.R
@@ -943,6 +943,13 @@ PetApi <- R6::R6Class(
 
       # explore
       for (query_item in `status`) {
+        # validate enum values
+        if (!(query_item %in% c("available", "pending", "sold"))) {
+          rlang::abort(message = "Invalid value for `status` when calling PetApi$find_pets_by_status. Must be [available, pending, sold].",
+                       .subclass = "ApiException",
+                       ApiException = ApiException$new(status = 0,
+                                                       reason = "Invalid value for `status` when calling PetApi$find_pets_by_status. Must be [available, pending, sold]."))
+        }
         query_params[["status"]] <- c(query_params[["status"]], list(`status` = query_item))
       }
 
diff --git a/samples/client/petstore/R/R/pet_api.R b/samples/client/petstore/R/R/pet_api.R
index df3e541a33d..c3d7f8f1d38 100644
--- a/samples/client/petstore/R/R/pet_api.R
+++ b/samples/client/petstore/R/R/pet_api.R
@@ -943,6 +943,13 @@ PetApi <- R6::R6Class(
 
       # explore
       for (query_item in `status`) {
+        # validate enum values
+        if (!(query_item %in% c("available", "pending", "sold"))) {
+          rlang::abort(message = "Invalid value for `status` when calling PetApi$FindPetsByStatus. Must be [available, pending, sold].",
+                       .subclass = "ApiException",
+                       ApiException = ApiException$new(status = 0,
+                                                       reason = "Invalid value for `status` when calling PetApi$FindPetsByStatus. Must be [available, pending, sold]."))
+        }
         query_params[["status"]] <- c(query_params[["status"]], list(`status` = query_item))
       }