Aim The serum lipids and apolipoproteins betweenthe hyperlipidemic and healthy residents in Beijing andGuangzhou were studied in order to find out the clue ofhigher incidence of cardiovascular diseases in Beijingthan that in the Guangzhou area.Methods Serum samples of 336 males (168 hyper-lipidemic cases and 168 healthy controls ) from Beijingsurvey field and 388 male subjects ( 194 hyperlipidemicand 194 healthy controls) from Guangzhou field werecollected respectively for the assays of total cholestetol(TC ), triglycerides (TG ) , high density lipoproteincholesterol (HDLC ) , HDL3-C, low density lipoproteincholesterol (LDLC) (by enzyme methods ) , apolipopro-teins B, AI (by immunoturbidimetric assay) and A Ⅵ(by ELISA).Results Most of the hyperlipidemic cases were hy-pertriglyceridemia in both areas. TC, apolipoprotein A Ⅵ were higher, but HDLC, mainly HDL₂C weremarkedly lower in cases of the hyperlipidemic than thatof the healthy control groups. There was no differ-ence seen about the apolipoprotein AI level betweenthe hyperlipidemic and control groups , anyhow, on theother hand, the TC, apolipoprotein B, HDLC andapolipoprotein AⅠ of the hyperlipidemic subjects weresignificantly lower in Beijing than that in Guangzhou ,and similar results were obtained in the healthy controlgroups in both areas.Conclusion High triglycerides and low HDL levelpredominated in the serum lipids of the hyperlipidemicsubjects in both Beijing and Guangzhou areas. Theimportant point is that the serum HDL and apolipopro-tein AⅠ levels were significantly lower in the residentsof Beijing which may contribute to the higher incidenceof coronary heart disease in Beijing than in theGuangzhou area.