A total of 25,650 Trisopterus minutus capelanus, poor cod, collected by trawling off the eastern coast of Greece (Fuvoikos Gulf, Pagassitikos Gulf and Orei Channel) between September 1986 and June 1988, were analysed. Otoliths from 457 specimens were used for age and growth studies together with length-frequency data. From the validation techniques, the analysis of marginal increments was selected. A single annulus forms each year on the otolith. Back-calculation of size at age showed that males were generally smaller than females, especially for fish more than one year old. The growth of poor cod was described by a von Bertalanffy growth curve with parameters K = 0.18, K = 0.32 and t0 = –1.83, t0 = –1.62 for females and males, respectively. The length-weight relationship was obtained for the total of individuals and b = 3.2 was used to estimate the condition factor. The condition factor has a maximal value in winter and decreases significantly during summer. The overall sex ratio shows a prevalence of females. Males begin to mature at size of between 10-11 cm and females between 11-12 cm. The spawning period extends from winter to summer with a peak during spring. The computed value of natural mortality was 0.44 and the mean total mortality rate for the two years studied was 0.87.