Butterfly Valley, or Wu Tip Kuk (Chinese: 蝴蝶谷), is a valley in north of Lai Chi Kok in New Kowloon of Hong Kong, located between O Pui Shan and Piper's Hill. The valley was a habitat of butterflies before Japanese occupation of Hong Kong and thus named after the creatures. During Japanese occupation between 1941 and 1945, the forest in valley was damaged by the Japanese military for obtaining wood. The butterflies lost their habitat and hence became extinct. The reforestation after war did not help to return the butterflies.