Testosterone cypionate, sold under the brand name Depo-Testosterone among others, is an androgen and anabolic steroid (AAS) medication which is used mainly in the treatment of low testosterone levels in men. It is also used in hormone therapy for transgender men. It is given by injection into muscle or subcutaneously, once every one to four weeks, depending on clinical indication.

Side effects of testosterone cypionate include symptoms of masculinization like acne, increased hair growth, voice changes, and increased sexual desire. The drug is a synthetic androgen and anabolic steroid and hence is an agonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT). It has strong androgenic effects and moderate anabolic effects, which make it useful for producing masculinization and suitable for androgen replacement therapy. Testosterone cypionate is a testosterone ester and a long-lasting prodrug of testosterone in the body. Because of this, it is considered to be a natural and bioidentical form of testosterone.

Testosterone cypionate was introduced for medical use in 1951. Along with testosterone enanthate, testosterone undecanoate, and testosterone propionate, it is one of the most commonly used testosterone esters. It is used mainly in the United States. In addition to its medical use, testosterone cypionate is used to improve physique and performance. The drug is a controlled substance in many countries and so non-medical use is generally illicit.