Abstract: Objective To use two commercially available lipoprotein( a) [ Lp(a)] particle concentration reagents to detect serum Lp(a) levels in apparently healthy population in Beijing, and to establish reference intervals for Lp( a) particle concentration detection methods. Methods A total of 415 healthy adults ( 215 males and 200 females ) with physical examination in Peking Union Medical College Hospital were selected as the research objects during November 2019 and August 2020, they were divided into 4 groups by different gae, respectively 16-44 years old, 45-59 yeas old, 60-74 years old and above 75 years old. The levels of 415 serum Lp(a) were detected by Mindray BS-800 (system A) and Roche Cobas 8000 ( system B) automatic biochemical analyzers and their matching two commercially available Lp(a) particle concentration reagents. Two systems were compared with the precision evaluation, Passing-Bablok regres sion analysis and Bland-Altman analysis method. Analyze the correlation of gender and age factors to the serum Ip(a)levels, and the percentile distribution of Lp( a) data by diferent stistcal methods according to the Lp(a) detection data type. In accordance with the requirements of the Clinical and Iaboratory Standards Institute (CLSI) C28-A3, the serum Lp( a) reference intervals of systems A and B were established respectively. Results The precisions of systems A and B were 1.3%-1.9%，0.9%-2.0%，and the intercept , slope , cofficient of detemination (R2 ), and correlation cofficient (r) of the regression equation were -0.013, 0.973,0.936, 0.967, the corelation is good. The bias graph showed that the average bias of two detection systems was 2.4%，and the expected bias at the medical decision level was - 2.69%. The serum Lp(a) test data of two systems A and B were non-normally distributed，and the median (P2s, P7s) were 16.73 (8.64, 46.52) nmol/L and 16.90 ( 8.80, 47 .40) nmol/L. The difference in serum Lp( a) levels between males and females was stistially signifcant (A: t=-2.121, P=0.034; B: t=-2.436, P=0.015). But the difference within 4 age groups was no statistically significant ( A: F=2.604, P=0.052; B: F=2.456, P=0.063 ). The reference intervals of Lp( a) particle concentration were calculated based on the