diff --git a/packages/primevue/src/fieldset/Fieldset.d.ts b/packages/primevue/src/fieldset/Fieldset.d.ts
index 2111ff7d0..b5d4ae110 100755
--- a/packages/primevue/src/fieldset/Fieldset.d.ts
+++ b/packages/primevue/src/fieldset/Fieldset.d.ts
@@ -199,6 +199,10 @@ export interface FieldsetSlots {
          * Collapsed state as a boolean
          */
         collapsed: boolean;
+        /**
+         * Style class of the icon.
+         */
+        class: string;
     }): VNode[];
     /**
      * Custom toggler icon template.
@@ -209,6 +213,10 @@ export interface FieldsetSlots {
          * Collapsed state as a boolean
          */
         collapsed: boolean;
+        /**
+         * Style class of the icon.
+         */
+        class: string;
     }): VNode[];
 }
 
diff --git a/packages/primevue/src/fieldset/Fieldset.vue b/packages/primevue/src/fieldset/Fieldset.vue
index 243ee61a0..9faa40eed 100755
--- a/packages/primevue/src/fieldset/Fieldset.vue
+++ b/packages/primevue/src/fieldset/Fieldset.vue
@@ -17,7 +17,7 @@
                     v-bind="{ ...toggleButtonProps, ...ptm('toggleButton') }"
                 >
                     <!--TODO: togglericon deprecated since v4.0-->
-                    <slot :name="$slots.toggleicon ? 'toggleicon' : 'togglericon'" :collapsed="d_collapsed">
+                    <slot :name="$slots.toggleicon ? 'toggleicon' : 'togglericon'" :collapsed="d_collapsed" :class="cx('toggleIcon')">
                         <component :is="d_collapsed ? 'PlusIcon' : 'MinusIcon'" :class="cx('toggleIcon')" v-bind="ptm('toggleIcon')" />
                     </slot>
                     <span :class="cx('legendLabel')" v-bind="ptm('legendLabel')">{{ legend }}</span>