diff --git a/api/core/plugin/entities/parameters.py b/api/core/plugin/entities/parameters.py
index bfa662b9f6..7d085e0106 100644
--- a/api/core/plugin/entities/parameters.py
+++ b/api/core/plugin/entities/parameters.py
@@ -79,6 +79,10 @@ class PluginParameter(BaseModel):
     default: Union[float, int, str, bool, list, dict] | None = None
     min: Union[float, int] | None = None
     max: Union[float, int] | None = None
+    multiple: bool | None = Field(
+        default=False,
+        description="Whether the parameter is multiple select, only valid for select or dynamic-select type",
+    )
     precision: int | None = None
     options: list[PluginParameterOption] = Field(default_factory=list)
 
@@ -112,8 +116,11 @@ def cast_parameter_value(typ: StrEnum, value: Any, /):
             ):
                 if value is None:
                     return ""
-                else:
-                    return value if isinstance(value, str) else str(value)
+                if isinstance(value, list):
+                    return value
+                if isinstance(value, str):
+                    return value
+                return str(value)
 
             case PluginParameterType.BOOLEAN:
                 if value is None:
diff --git a/api/core/workflow/nodes/tool/entities.py b/api/core/workflow/nodes/tool/entities.py
index c1cfbb1edc..0bf274115c 100644
--- a/api/core/workflow/nodes/tool/entities.py
+++ b/api/core/workflow/nodes/tool/entities.py
@@ -54,8 +54,8 @@ class ToolNodeData(BaseNodeData, ToolEntity):
                 for val in value:
                     if not isinstance(val, str):
                         raise ValueError("value must be a list of strings")
-            elif typ == "constant" and not isinstance(value, str | int | float | bool | dict):
-                raise ValueError("value must be a string, int, float, bool or dict")
+            elif typ == "constant" and not isinstance(value, str | int | float | bool | list | dict):
+                raise ValueError("value must be a string, int, float, bool, list or dict")
             return typ
 
     tool_parameters: dict[str, ToolInput]
diff --git a/web/app/components/header/account-setting/model-provider-page/declarations.ts b/web/app/components/header/account-setting/model-provider-page/declarations.ts
index a5dd46b59f..243570da26 100644
--- a/web/app/components/header/account-setting/model-provider-page/declarations.ts
+++ b/web/app/components/header/account-setting/model-provider-page/declarations.ts
@@ -121,6 +121,7 @@ export type CredentialFormSchemaBase = {
   label: TypeWithI18N
   type: FormTypeEnum
   required: boolean
+  multiple?: boolean
   default?: string
   tooltip?: TypeWithI18N
   show_on: FormShowOnObject[]
diff --git a/web/app/components/workflow/nodes/_base/components/form-input-item.tsx b/web/app/components/workflow/nodes/_base/components/form-input-item.tsx
index 419f905fa5..65299911d9 100644
--- a/web/app/components/workflow/nodes/_base/components/form-input-item.tsx
+++ b/web/app/components/workflow/nodes/_base/components/form-input-item.tsx
@@ -110,6 +110,8 @@ const FormInputItem: FC<Props> = ({
       return VarType.arrayFile
     else if (type === FormTypeEnum.file)
       return VarType.file
+    else if (isMultipleSelect)
+      return VarType.array
     else if (isSelect)
       return VarType.string
     // else if (isAppSelector)
@@ -129,6 +131,8 @@ const FormInputItem: FC<Props> = ({
   const getFilterVar = () => {
     if (isNumber)
       return (varPayload: any) => varPayload.type === VarType.number
+    else if (isMultipleSelect)
+      return (varPayload: any) => [VarType.array, VarType.arrayString, VarType.arrayNumber, VarType.arrayObject].includes(varPayload.type)
     else if (isString)
       return (varPayload: any) => [VarType.string, VarType.number, VarType.secret].includes(varPayload.type)
     else if (isFile)