diff --git a/packages/backend/src/server/api/endpoints/charts/user/following.ts b/packages/backend/src/server/api/endpoints/charts/user/following.ts
index 0a019ce4fb..67efc83246 100644
--- a/packages/backend/src/server/api/endpoints/charts/user/following.ts
+++ b/packages/backend/src/server/api/endpoints/charts/user/following.ts
@@ -3,19 +3,29 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-import { Injectable } from '@nestjs/common';
+import { Injectable, Inject } from '@nestjs/common';
+import { DI } from '@/di-symbols.js';
+import type { UserProfilesRepository } from '@/models/_.js';
+import { UserEntityService } from '@/core/entities/UserEntityService.js';
+import { RoleService } from '@/core/RoleService.js';
 import { Endpoint } from '@/server/api/endpoint-base.js';
 import { getJsonSchema } from '@/core/chart/core.js';
 import PerUserFollowingChart from '@/core/chart/charts/per-user-following.js';
 import { schema } from '@/core/chart/charts/entities/per-user-following.js';
+import { ApiError } from '@/server/api/error.js';
 
 export const meta = {
 	tags: ['charts', 'users', 'following'],
 
 	res: getJsonSchema(schema),
 
-	allowGet: true,
-	cacheSec: 60 * 60,
+	errors: {
+		ffIsMarkedAsPrivate: {
+			message: 'This user\'s followings and/or followers is marked as private.',
+			code: 'FF_IS_MARKED_AS_PRIVATE',
+			id: '52e90f27-3dfd-441e-a1f2-ca6ac7068040',
+		},
+	},
 } as const;
 
 export const paramDef = {
@@ -32,10 +42,48 @@ export const paramDef = {
 @Injectable()
 export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-disable-line import/no-default-export
 	constructor(
+		@Inject(DI.userProfilesRepository)
+		private userProfilesRepository: UserProfilesRepository,
+
+		private roleService: RoleService,
+		private userEntityService: UserEntityService,
 		private perUserFollowingChart: PerUserFollowingChart,
 	) {
 		super(meta, paramDef, async (ps, me) => {
-			return await this.perUserFollowingChart.getChart(ps.span, ps.limit, ps.offset ? new Date(ps.offset) : null, ps.userId);
+			const done = async () => {
+				return await this.perUserFollowingChart.getChart(ps.span, ps.limit, ps.offset ? new Date(ps.offset) : null, ps.userId);
+			};
+
+			if (me != null && me.id === ps.userId) {
+				return await done();
+			}
+
+			const profile = await this.userProfilesRepository.findOneByOrFail({ userId: ps.userId });
+
+			if (profile.followingVisibility === 'public' && profile.followersVisibility === 'public') {
+				return await done();
+			}
+
+			const iAmModerator = await this.roleService.isModerator(me);
+
+			if (iAmModerator) {
+				return await done();
+			}
+
+			if (
+				me != null && (
+					(profile.followingVisibility === 'followers' && profile.followersVisibility === 'followers') ||
+					(profile.followingVisibility === 'followers' && profile.followersVisibility === 'public') ||
+					(profile.followingVisibility === 'public' && profile.followersVisibility === 'followers')
+				)
+			) {
+				const relations = await this.userEntityService.getRelation(me.id, ps.userId);
+				if (relations.following) {
+					return await done();
+				}
+			}
+
+			throw new ApiError(meta.errors.ffIsMarkedAsPrivate);
 		});
 	}
 }
diff --git a/packages/frontend/src/components/MkChart.vue b/packages/frontend/src/components/MkChart.vue
index d05f4921f6..2302e6c16a 100644
--- a/packages/frontend/src/components/MkChart.vue
+++ b/packages/frontend/src/components/MkChart.vue
@@ -53,7 +53,7 @@ export type ChartSrc =
 import { onMounted, ref, shallowRef, watch } from 'vue';
 import { Chart } from 'chart.js';
 import * as Misskey from 'misskey-js';
-import { misskeyApiGet } from '@/scripts/misskey-api.js';
+import { misskeyApiGet, misskeyApi } from '@/scripts/misskey-api.js';
 import { defaultStore } from '@/store.js';
 import { useChartTooltip } from '@/scripts/use-chart-tooltip.js';
 import { chartVLine } from '@/scripts/chart-vline.js';
@@ -758,7 +758,10 @@ const fetchPerUserPvChart = async (): Promise<typeof chartData> => {
 };
 
 const fetchPerUserFollowingChart = async (): Promise<typeof chartData> => {
-	const raw = await misskeyApiGet('charts/user/following', { userId: props.args?.user?.id, limit: props.limit, span: props.span });
+	const raw = await misskeyApi('charts/user/following', { userId: props.args?.user?.id!, limit: props.limit, span: props.span }).catch(() => {
+		return null;
+	});
+	if (raw == null) return null;
 	return {
 		series: [{
 			name: 'Local',
@@ -773,7 +776,10 @@ const fetchPerUserFollowingChart = async (): Promise<typeof chartData> => {
 };
 
 const fetchPerUserFollowersChart = async (): Promise<typeof chartData> => {
-	const raw = await misskeyApiGet('charts/user/following', { userId: props.args?.user?.id, limit: props.limit, span: props.span });
+	const raw = await misskeyApi('charts/user/following', { userId: props.args?.user?.id!, limit: props.limit, span: props.span }).catch(() => {
+		return null;
+	});
+	if (raw == null) return null;
 	return {
 		series: [{
 			name: 'Local',
diff --git a/packages/frontend/src/pages/user/activity.following.vue b/packages/frontend/src/pages/user/activity.following.vue
index aa2c791c76..15963f0aaa 100644
--- a/packages/frontend/src/pages/user/activity.following.vue
+++ b/packages/frontend/src/pages/user/activity.following.vue
@@ -32,7 +32,7 @@ const props = defineProps<{
 	user: Misskey.entities.User;
 }>();
 
-const chartEl = shallowRef<HTMLCanvasElement>(null);
+const chartEl = shallowRef<HTMLCanvasElement>();
 const legendEl = shallowRef<InstanceType<typeof MkChartLegend>>();
 const now = new Date();
 let chartInstance: Chart = null;
@@ -88,7 +88,7 @@ async function renderChart() {
 		}, extra);
 	}
 
-	chartInstance = new Chart(chartEl.value, {
+	chartInstance = new Chart(chartEl.value!, {
 		type: 'bar',
 		data: {
 			datasets: [
diff --git a/packages/frontend/src/pages/user/activity.vue b/packages/frontend/src/pages/user/activity.vue
index 994bd52705..f555d72132 100644
--- a/packages/frontend/src/pages/user/activity.vue
+++ b/packages/frontend/src/pages/user/activity.vue
@@ -14,7 +14,10 @@ SPDX-License-Identifier: AGPL-3.0-only
 			<template #header><i class="ti ti-pencil"></i> Notes</template>
 			<XNotes :user="user"/>
 		</MkFoldableSection>
-		<MkFoldableSection class="item">
+		<MkFoldableSection
+			v-if="isFollowersVisibleForMe(user) && isFollowingVisibleForMe(user)"
+			class="item"
+		>
 			<template #header><i class="ti ti-users"></i> Following</template>
 			<XFollowing :user="user"/>
 		</MkFoldableSection>
@@ -33,9 +36,10 @@ import XNotes from './activity.notes.vue';
 import XFollowing from './activity.following.vue';
 import MkFoldableSection from '@/components/MkFoldableSection.vue';
 import MkHeatmap from '@/components/MkHeatmap.vue';
+import { isFollowersVisibleForMe, isFollowingVisibleForMe } from '@/scripts/isFfVisibleForMe.js';
 
 const props = defineProps<{
-	user: Misskey.entities.User;
+	user: Misskey.entities.UserDetailed;
 }>();
 
 </script>
diff --git a/packages/misskey-js/src/autogen/types.ts b/packages/misskey-js/src/autogen/types.ts
index a5333d4f93..8ce154b086 100644
--- a/packages/misskey-js/src/autogen/types.ts
+++ b/packages/misskey-js/src/autogen/types.ts
@@ -1227,13 +1227,6 @@ export type paths = {
     post: operations['charts___user___drive'];
   };
   '/charts/user/following': {
-    /**
-     * charts/user/following
-     * @description No description provided.
-     *
-     * **Credential required**: *No*
-     */
-    get: operations['charts___user___following'];
     /**
      * charts/user/following
      * @description No description provided.