A B S T R A C T A comparative study on the effect of chemical fertilizers and bio-fertilizers was done on growth and biochemical parameters in cucumber plant (Cucumis sativus).An experiment was conducted in Randomized Completely Blocks Design (RCBD) with four replicates. The treatment were (T1 = Control, T2 = Bio-fertilizer, T3 = Chemical and T4 = Combination treatment (biofertilizer and 1/2 chemical)) at Agricultural Technical Institute of Bakrajo, Sulaymania, Iraq during 2014. The bio-fertilizer used in this study was Azoto barwar1 and chemical fertilizer was urea. The material consisted of one cultivar of cucumber sayfe species. The results indicated that there were significant difference between the application bio-fertilizer and chemical fertilizer for yield and yield component traits. Comparison means were conducted by Duncan method. This study indicated that a combination treatment of bio-fertilizer and chemical fertilizer had significant effect and increased the yield and growth traits of cucumber. The correlation analysis showed that the strongest positive relationship was between fruit yield and total fruit weight per plant (r = 0.89). The results of regression analysis by stepwise method for fruit yield in cucumber indicated that individual fruit weigh can justify 50.9% of the fruit yield variation. According to this study using bio-fertilizers has increased yield and yield component of cucumber significantly.