This study was carried out between March 2007 and April 2008 in Karasu Stream. Total 472 individual sampled by hand nets and electroshock. Length, weight, sex and gonad weight were determined. Age was determined by scales. The age, length and weights of samples varied from I-VI, 4.0-37.5 cm and 0.7-676.2 g, respectively. It was determined that the most samples were in 12.0-13.9 cm (16.1%) and 0-24.9 g (21.2%) group. Condition factor, length-weight, age-length, age-weight equations, mate:female ration were calculated as 1.452, W = 0.0129xL(3.039), Lt = 52.58x[1-e(-0.145x(1+0.464))], Wt = 2188.21x[1-e(-0.145x(1+0.464))](3.039), 2.603, 1:0.85, respectively. Sexual maturity size was determined as in males I I cm, in females 23 cm. In the reproduction, period reproduction nods were seen on head and anal fins of males. Relative fecundity number calculated as 44494 number kg(-1) fish and age diameter measured as 2.011 mm.