diff --git a/dlls/jscript/function.c b/dlls/jscript/function.c
index 4c07cb3e587..7d39ad05893 100644
--- a/dlls/jscript/function.c
+++ b/dlls/jscript/function.c
@@ -369,7 +369,21 @@ static const builtin_info_t Function_info = {
     NULL
 };
 
-static HRESULT create_function(script_ctx_t *ctx, DWORD flags, DispatchEx *prototype, FunctionInstance **ret)
+static HRESULT FunctionConstr_value(DispatchEx *dispex, LCID lcid, WORD flags, DISPPARAMS *dp,
+        VARIANT *retv, jsexcept_t *ei, IServiceProvider *sp)
+{
+    FIXME("\n");
+    return E_NOTIMPL;
+}
+
+static HRESULT FunctionProt_value(DispatchEx *dispex, LCID lcid, WORD flags, DISPPARAMS *dp,
+        VARIANT *retv, jsexcept_t *ei, IServiceProvider *sp)
+{
+    FIXME("\n");
+    return E_NOTIMPL;
+}
+
+static HRESULT create_function(script_ctx_t *ctx, DWORD flags, BOOL funcprot, DispatchEx *prototype, FunctionInstance **ret)
 {
     FunctionInstance *function;
     HRESULT hres;
@@ -378,7 +392,10 @@ static HRESULT create_function(script_ctx_t *ctx, DWORD flags, DispatchEx *proto
     if(!function)
         return E_OUTOFMEMORY;
 
-    hres = init_dispex(&function->dispex, ctx, &Function_info, NULL);
+    if(funcprot)
+        hres = init_dispex(&function->dispex, ctx, &Function_info, prototype);
+    else
+        hres = init_dispex_from_constr(&function->dispex, ctx, &Function_info, ctx->function_constr);
     if(FAILED(hres))
         return hres;
 
@@ -410,7 +427,7 @@ HRESULT create_builtin_function(script_ctx_t *ctx, builtin_invoke_t value_proc,
     FunctionInstance *function;
     HRESULT hres;
 
-    hres = create_function(ctx, flags, prototype, &function);
+    hres = create_function(ctx, flags, FALSE, prototype, &function);
     if(FAILED(hres))
         return hres;
 
@@ -433,7 +450,7 @@ HRESULT create_source_function(parser_ctx_t *ctx, parameter_t *parameters, sourc
     if(FAILED(hres))
         return hres;
 
-    hres = create_function(ctx->script, PROPF_CONSTR, prototype, &function);
+    hres = create_function(ctx->script, PROPF_CONSTR, FALSE, prototype, &function);
     jsdisp_release(prototype);
     if(FAILED(hres))
         return hres;
@@ -456,3 +473,24 @@ HRESULT create_source_function(parser_ctx_t *ctx, parameter_t *parameters, sourc
     *ret = &function->dispex;
     return S_OK;
 }
+
+HRESULT init_function_constr(script_ctx_t *ctx)
+{
+    FunctionInstance *prot, *constr;
+    HRESULT hres;
+
+    hres = create_function(ctx, PROPF_CONSTR, TRUE, NULL, &prot);
+    if(FAILED(hres))
+        return hres;
+
+    prot->value_proc = FunctionProt_value;
+
+    hres = create_function(ctx, PROPF_CONSTR, TRUE, &prot->dispex, &constr);
+    jsdisp_release(&prot->dispex);
+    if(FAILED(hres))
+        return hres;
+
+    constr->value_proc = FunctionConstr_value;
+    ctx->function_constr = &constr->dispex;
+    return hres;
+}
diff --git a/dlls/jscript/global.c b/dlls/jscript/global.c
index 70983fcbb26..4404bffe8c3 100644
--- a/dlls/jscript/global.c
+++ b/dlls/jscript/global.c
@@ -106,8 +106,9 @@ static HRESULT JSGlobal_Date(DispatchEx *dispex, LCID lcid, WORD flags, DISPPARA
 static HRESULT JSGlobal_Function(DispatchEx *dispex, LCID lcid, WORD flags, DISPPARAMS *dp,
         VARIANT *retv, jsexcept_t *ei, IServiceProvider *sp)
 {
-    FIXME("\n");
-    return E_NOTIMPL;
+    TRACE("\n");
+
+    return constructor_call(dispex->ctx->function_constr, lcid, flags, dp, retv, ei, sp);
 }
 
 static HRESULT JSGlobal_Number(DispatchEx *dispex, LCID lcid, WORD flags, DISPPARAMS *dp,
@@ -332,6 +333,10 @@ static HRESULT init_constructors(script_ctx_t *ctx)
 {
     HRESULT hres;
 
+    hres = init_function_constr(ctx);
+    if(FAILED(hres))
+        return hres;
+
     hres = create_array_constr(ctx, &ctx->array_constr);
     if(FAILED(hres))
         return hres;
diff --git a/dlls/jscript/jscript.h b/dlls/jscript/jscript.h
index 603b27996ba..6c4e2723b80 100644
--- a/dlls/jscript/jscript.h
+++ b/dlls/jscript/jscript.h
@@ -165,6 +165,7 @@ struct _script_ctx_t {
 
     DispatchEx *script_disp;
     DispatchEx *global;
+    DispatchEx *function_constr;
     DispatchEx *array_constr;
     DispatchEx *bool_constr;
     DispatchEx *number_constr;
@@ -181,6 +182,7 @@ static inline void script_addref(script_ctx_t *ctx)
 }
 
 HRESULT init_global(script_ctx_t*);
+HRESULT init_function_constr(script_ctx_t*);
 
 HRESULT create_array_constr(script_ctx_t*,DispatchEx**);
 HRESULT create_bool_constr(script_ctx_t*,DispatchEx**);
diff --git a/dlls/jscript/tests/lang.js b/dlls/jscript/tests/lang.js
index 3a24864b753..83732a2721b 100644
--- a/dlls/jscript/tests/lang.js
+++ b/dlls/jscript/tests/lang.js
@@ -79,6 +79,12 @@ ok(Number.prototype !== undefined, "Number.prototype is undefined");
 ok(RegExp.prototype !== undefined, "RegExp.prototype is undefined");
 ok(Math !== undefined, "Math is undefined");
 ok(Math.prototype === undefined, "Math.prototype is not undefined");
+ok(Function.prototype !== undefined, "Function.prototype is undefined");
+ok(Function.prototype.prototype === undefined, "Function.prototype is not undefined");
+
+Function.prototype.test = true;
+ok(testFunc1.test === true, "testFunc1.test !== true");
+ok(Function.test === true, "Function.test !== true");
 
 ok(typeof(0) === "number", "typeof(0) is not number");
 ok(typeof(1.5) === "number", "typeof(1.5) is not number");