Polymers of individual and mixed normal C-12, C-14, C-16, and C-18 alpha-olefins are synthesized, purified, and then characterized. The performance of poly-alpha-olefins is assessed for improving the cold flow properties of a local gas oil in terms of cloud-point and pour-point depression. Results show that poly-alpha-olefins have great potency in decreasing the pour point of the distillate fuel, whereas a slight effect is observed in decreasing the cloud point. Efficiency of the polymeric pour-point depressants is discussed on the basis of their structure and average molecular weight.