Disclosed is a leukocyte removal filter that comprises a non-woven fabric containing a polybutylene terephthalate fiber, wherein the average fiber size of the non-woven fabric is 0.9-1.5 μm, the texture index corresponding to a thickness of 0.3 mm of the non-woven fabric is 15-70, and relational expression (1) is satisfied:Y≥-0.65 × X + 1.75 ... (1)wherein X represents the average fiber size of the non-woven fabric and Y represents the specific surface area of the non-woven fabric.
