Background : Hemolysis is the most common pre–analytical error encountered in biochemistry laboratories.The aim of the present study was to evaluate the effect of visible hemolysis on biochemistry parameters done in the emergency laboratory. Materials and methods : 150 blood samples (50 highly hemolyzed, 50 slightly hemolyzed and 50 no hemolysis ) received in the Emergency Biochemistry laboratory of Safdarjung Hospital,New Delhi, were included in the study .They were analyzed for different biochemical parameters and the results compared. Results : No significant change is seen samples with slight hemolysis. However, values of potassium, total and direct bilirubin are significantly elevated and ALPis decreased in samples that are highly hemolyzed. Conclusion: Test values of slightly hemolyzed samples can be reported as there is little interference seen. However, in case of highly hemolyzed samples , values of ALP, potassium, total and direct bilirubin should not be reported.