diff --git a/src/client/components/ui/context-menu.vue b/src/client/components/ui/context-menu.vue
index 3a11589e8..1b4d386eb 100644
--- a/src/client/components/ui/context-menu.vue
+++ b/src/client/components/ui/context-menu.vue
@@ -35,8 +35,30 @@ export default defineComponent({
 		},
 	},
 	mounted() {
-		this.$el.style.top = this.ev.pageY + 'px';
-		this.$el.style.left = this.ev.pageX + 'px';
+		let left = this.ev.pageX + 1; // 間違って右ダブルクリックした場合に意図せずアイテムがクリックされるのを防ぐため + 1
+		let top = this.ev.pageY + 1; // 間違って右ダブルクリックした場合に意図せずアイテムがクリックされるのを防ぐため + 1
+
+		const width = this.$el.offsetWidth;
+		const height = this.$el.offsetHeight;
+
+		if (left + width - window.pageXOffset > window.innerWidth) {
+			left = window.innerWidth - width + window.pageXOffset;
+		}
+
+		if (top + height - window.pageYOffset > window.innerHeight) {
+			top = window.innerHeight - height + window.pageYOffset;
+		}
+
+		if (top < 0) {
+			top = 0;
+		}
+
+		if (left < 0) {
+			left = 0;
+		}
+
+		this.$el.style.top = top + 'px';
+		this.$el.style.left = left + 'px';
 
 		for (const el of Array.from(document.querySelectorAll('body *'))) {
 			el.addEventListener('mousedown', this.onMousedown);