Oil red O staining and analysis of cell image are used to quantitate and compare the uptake of oxidized low density lipoprotein (OLDL)bymoues peritoneal macrophages under different cultural conditions. The results show that absence of LDL (1640 medium contains 5 percent BSA) and OLDL preincubation enhances the uptake of OLDL by 25 and 105 percent respectively, while high concentration of LDL (1640 medium contains 200 mg. L-1 LDL) or 1 g ·L-1 BCG preincubation decrease the uptake by 46percent and 26 percent. No predminant alteration occurs after pretreatment of 100 mg·L-1 SiO2. The results suggest that absence of LDL and OLDL preincubation induce the scavenger receptor activity, while high concentration of LDL or BCG suppress those receptors.