A polymer membrane for delivering a drug is provided. The membrane is capable of regulating the delivery of the drug and comprises (A) a porous hydrophobic polymer membrane having a pore diameter of not larger than 3 mu m and a porosity of 10 to 90% which is immobilized with (B) a specific liquid crystal-forming compound having a gel/liquid crystal transition temperature in the range of 25 DEG to 45 DEG C.
