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 an 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.
The lower section of the valley was the site of a demolished squatter of Wai Man Tsuen (衛民村). The site now on the construction of Route 8. The upper section is part of country park.
On the side above Piper's Hill, there are Roman Catholic Cemetery, Yew Chung International School of Hong Kong. On another side above O Pui Shan is O Pui Shan Boy's Home.
There is a river run along the valley. Its upper course was blocked for collecting water in Kowloon Reservoirs and its lower course become a covered nullah under Butterfly Valley Road, which is the border of Lai Chi Kok and Cheung Sha Wan.
Although its proximity to Lai Chi Kok, large part of valley belongs to Kwai Tsing District.