The study aims to investigate some reproductive properties of bullet tuna (Auxis rochei) in Turkish waters. A total of 216 bullet tunas, 110 males (50.93%) and 106 females (49.07%), from the Turkish Mediterranean coasts were sampled monthly between December 2008 and December 2009. The sex ratio was 1:1.04. A total of 106 ovaries were obtained from the females, and these ovaries were histologically examined to determine the reproductive conditions and developmental stages of oocytes. The gonado-somatic index (GSI) values calculated for females indicated that spawning generally occurred between May and September. The most intensive spawning period was observed between June and August. A total of 40 females collected between May and September were sexually mature.