Background: The relation between elevated lipoprotein(a) [Lp(a)] and future atherosclerotic cardiovascular disease (ASCVD) in those with vs. without diabetes mellitus (DM) but known cardiovascular disease (CVD) is not clear. We examined recurrent ASCVD event risk by DM status in persons with known CVD on statin therapy. Methods: We studied 1,354 patients with and 2,005 patients without DM, all with prior CVD on statin therapy in the AIM-HIGH cohort. First and total recurrent ASCVD event rates were calculated by Lp(a) levels and the PWP model provided hazard ratios (HRs) for events over a mean follow-up of 3.3 years, adjusted for age, sex, trial treatment, LDL-C, and other risk factors. Results: ASCVD event rates (per 1000 person years) increased with Lp(a) levels ranging from <15 mg/dl to ≥70 mg/dL in non-DM: 39.7 to 74.1 for first and 48.5 to 87.3 for total recurrent events and in DM: 51.1 to 79.5 for first and 69.8 to 100.3 for total recurrent events. The Table shows HRs by Lp(a) categories for first and total recurrent ASCVD events. A higher risk for first recurrent events is noted at lower Lp(a) levels in those with vs. without DM. Conclusions: Higher Lp(a) levels predict residual ASCVD risk. However, ASCVD event risk may occur at lower levels of Lp(a) in those with vs. without DM. Future investigations in larger cohorts are needed to confirm these findings. Disclosure Y. Zhao: None. J.C. Sung: Employee; Self; Novartis Pharmaceuticals Corporation. A. Browne: Employee; Self; Novartis Pharmaceuticals Corporation. N.D. Wong: Advisory Panel; Self; Esperion Therapeutics, Inc. Research Support; Self; Amarin Corporation, Amgen, Boehringer Ingelheim Pharmaceuticals, Inc., Novartis AG, Novo Nordisk Inc. Speaker’s Bureau; Self; Amarin Corporation, Sanofi.