Thung Khru (Thai: ทุ่งครุ, pronounced [tʰûŋ kʰrúʔ]) is one of the 50 districts (khet) of Bangkok, Thailand.

The district is bounded by (clockwise from north) Rat Burana District of Bangkok, Amphoe Phra Pradaeng and Amphoe Phra Samut Chedi of Samut Prakan province, Bang Khun Thian and Chom Thong of Bangkok.

Khet Thung Khru is a second-order administrative division.

It is thought that khru here stands for a kind of utensil woven and coated for water transport, hence an indication that the area was once famous for the handicraft.

Neighboring districts are (from the west clockwise) Thung Khru, Rat Burana, Yan Nawa, Khlong Toei, Phra Khanong, and Bang Na (all Bangkok), and the districts Mueang Samut Prakan and Phra Samut Chedi of Samut Prakan.