The aim of this study was to examine concentration and composition of lipoproteins and levels of apolipoproteins in serum of 46 lacto-ovo-vegetarians in comparison with 49 non-vegetarians. Other clinical-chemistry parameters were also included in this study. Both male and female lacto-ovo-vegetarians showed a favourable lipoprotein profile characterized by low concentrations of atherogenic LDL-cholesterol, low ratios of cholesterol/HDL-cholesterol, LDL-cholesterol/ HDL-cholesterol and a high ratio HDL 2 -cholesterol/HDL 3 -chol-esterol. The favourable lipoprotein profile of vegetarians manifested as a low ratio of apolipoprotein B/apolipoprotein A-I and a low concentration of lipoprotein particles containing apolipoprotein B together with apo C-III. These parameters were significantly different between the vegetarians and the non-vegetarians.The α-tocopherol/LDL-cholesterol molar ratio was significantly higher in vegetarians in comparison with non-vegetarians which may be important with respect to protection against atherosclerosis. Total and free carnitine concentrations were reduced in serum of lacto-ovo-vegetarians. However this small reduction does not reflect a carnitine deficiency. The favourable serum lipoprotein profile among vegetarians observed in this study may result not only from nutritional conditions but also from special life-style factors within this group.