Kan Palungkrathok, 22, was arrested shortly after he took seven Bt100 banknotes from the tree in front of a noodle shop on Soi Wutthakart 40 in Jom Thong district.
The tree was set up to collect donations for Wat Kuang Muen in Chiang Mai.
Police said Kan admitted to having stolen money from the same tree just last week, taking Bt300 to buy methamphetamine.
Thai Buddhists consider stealing money intended for temples a grave sin.