To develop a new contraceptive implant containing gestodene featuring with only one rod for 5 years long effectiveness and safety. Gestodene synthesis, polymer tube designation, in vitro or in vivo test, the pilot test was used for the establishing of minimum clinic dosage. It had a burst effect at beginning and become constantly releasing since 12th day. It had zero-order releasing, in vitro, the average releasing rate was 17.0-19.1 μg/d, the safe dosage was 70.2mg/kg, C 1hr was 2.91 ± 1.25 ng/ml, T max was 8.86 ± 4.32 h, C max was 7.31 ± 1.09 ng/ml, T ss was 14 d, Css was 4.16 ± 0.48 ng/ml. Twenty-four hours later after removal of the implant, gestodene was almost cleaned out in the blood circulation and only trace amount of drug was detected after the removal. One rod gestodene implant is a new long effective contraceptive and may be promising.