Yi Tung Shan, Mountain summit on Lantau Island, Hong Kong.

Yi Tung Shan is a 752-metre peak in eastern Lantau Island, Hong Kong, standing west of Sunset Peak (Tai Tung Shan). Stage 2 of the Lantau Trail crosses the northern side of the summit. The Chinese sources rank it as Hong Kong's eighth-highest mountain, while the English source places it ninth.

Yi Tung Shan was originally named Yi Lim Shan (二楝山); the current form 二東山 means "Second East Mountain", paired with Tai Tung Shan (大東山, "Big East Mountain") for neighbouring Sunset Peak. The Cantonese reading is Ji6 Tung1 Saan1. The peak appears in Hong Kong's official height rankings, listed as eighth in Chinese sources and ninth in English ones.

The Cantonese name Yi Tung Shan means "Second East Mountain", paired with Sunset Peak's Tai Tung Shan, "Big East Mountain". Stage 2 of the Lantau Trail crosses the mountain's northern slope, so through-hikers pass below the summit rather than over it.

Hikers should expect a challenging ascent and descent that requires physical endurance. It is wise to start early to make best use of daylight and to ensure a safe return from the summit.

Yi Tung Shan was originally called Yi Lim Shan (二楝山); the name changed to Yi Tung Shan, meaning "Second East Mountain", to pair with Sunset Peak's Cantonese name Tai Tung Shan, "Big East Mountain". The two peaks stand side by side on eastern Lantau, with Yi Tung Shan west of the higher Sunset Peak.