Testosterone acetylsalicylate(TA) given(i.m. 3.0×10^-5mol/kg) to cas trated rats displayed androgenic and anabolie activities with a mild and persistent effect, The separate androgenic and anabolic effects were noted in a study on the course of the action of TA(i.m. 7.5×10^-5mol/kg), There was a linear corelationship between response and log dose of TA in the dose range studied, TA given orally(36.0×10^-6mol/kg) was not so potent as that given i.m.(3.0×10^-5mol/kg). The authors presume that TA might be clinically useful in androgen therapy.