Aspects of the productive biology and size at first sexual maturity of female Parapenaeus longirostris were analysed from monthly samples collected by deep trawling in Babadillimam Bight in the northeastern Mediterranean, from June 1999 to April 2000. Ripe females were found to be present between November and June. The spawning season ranged from the end of autumn through the winter (December-March) to the begining of summer (April-June). The minimum female size at maturity (carapace length) was 13.4 mm, and 50% of the female population was mature at about 18.2 mm (CL50). Fecundity ranged from 12 300 to 125 600 eggs for individuals, with a mean fecundity of 49 127 +/- 12 524.