Guy Henry Bullock (23 July 1887 - 12 April 1956) was a British diplomat who is best known for his participation in the 1921 British Mount Everest reconnaissance expedition. As expedition mountaineers, he and George Mallory found a northern access route to Everest by climbing the Lhakpa La col above the East Rongbuk Glacier and by going on to reach the North Col at . They did not, however, reach the summit of Mount Everest.