The present study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh during the period of July 2006 to June 2007 to evaluate the effect of pregnancy on serum LDL-cholesterol. The serum concentrations of LDL-cholesterol was measured in 100cases during their 2nd and 3rd trimester of pregnancy and in a control group of 100 cases of non pregnant women which was matched on reproductive age. Data were analyzed by computer with SPSS program using unpaired student 't' test. The result showed that the pregnant women had significantly higher concentrations of serum LDL-cholesterol. Higher concentrations of serum LDL-cholesterol was more common in pregnant than control and reaching maximum at 3rd trimester of pregnancy. This may be a purely physiological response to pregnancy or it may be indicative of pathology in some women. These results warrant a follow up study to investigative whether the LDL hypercholesterolemia persists after parturition.