Proprotein convertase subtilisin/kexin type 9 monoclonal antibodies (PCSK9 mAb) lower low-density lipoprotein cholesterol (LDL-C) levels and reduce atherosclerotic cardiovascular disease (ASCVD). Data regarding sex differences in PCSK9 mAb treatment remain lacking. This study examines sex differences in patients' characteristics, indications, efficacy, and safety of PCSK9 mAb treatment. Retrospective study based on data from the Preventive Cardiology and Lipids Clinic in Rabin Medical Center on patients prescribed with PCSK9 mAb. Collected data included medical background, medications, indications and laboratory data, analyzed by sex. 246 patients were included (mean age 67y, ASCVD 78.8 %, mean baseline LDL-C 128.2 mg/dL). Women (42 %) prescribed with PCSK9 mAb were older (69y vs. 65y, respectively; p < 0.001) and had higher baseline LDL-C (138.9 vs. 117.3 mg/dL; p < 0.001) than men. The dominant indication for PCSK9 mAb therapy in both sexes was secondary prevention, however, primary prevention was more prevalent in women (39.4 % vs. 16.3 %, respectively; p < 0.001). Overall, high adherence to treatment was observed without sex differences (91.8 % and 79.7 % at 3 and 12 months, respectively). After 1-year, adherent women had higher LDL-C levels than adherent men (61.9 vs. 46.8 mg/dL, respectively; P = 0.001), and were less likely to reach their LDL-C goals; >70 mg/dL (62.2 % vs. 76.1 %, respectively; P = 0.032) and > 55 mg/dL (39.8 % vs. 60.1 % respectively; P = 0.003). PCSK9 mAbs treatment demonstrated sex differences in prescription age, indications, baseline LDL-C and achievement of LDL-C goals. Adherence to PCSK9 mAb therapy was higher than previously reported, possibly due to careful surveillance strategy in a dedicated prevention clinic.