Introduction: Infective endocarditis is a severe condition that can occur after invasive dental procedures, mainly in patients with prosthetic heart valves and rheumatic and congenital heart disease. It is important to identify the level of knowledge of dental students to establish reforms in the curriculum of the career. Objective: To determine the level of knowledge about antibiotic prophylaxis of infective endocarditis prior to dental procedures in lastyear dental students of Lima. Material and methods: Analytical and crosssectional study whose sample was made up of 117 last-year dental students of the National University of San Marcos (UNMSM), the National University Federico Villareal (UNFV) and the Peruvian University Cayetano Heredia (UPCH) from Lima, Peru, during the year 2014. The evaluation instrument was a survey of 20 closed questions on epidemiology and etiopathogenesis of infective endocarditis and indication and pharmacology of antibiotic prophylaxis prior to dental procedures. The results were cataloged in 3 levels: low, regular and high. Results: The results show that 53,84 % of the interns presented a low level of knowledge, while 32,47 % had a regular level and 13,69 % a high level. The average response level was 10,1 ± 2,95 [95 % CI (9,57-10,65)]. By university, UNMSM interns had an average level of knowledge of 11 ± 2,60 [95 % CI (9,84-12,15)], UNFV had 8,8 ± 3,36 [95 % CI (7,74-9,86)] and those of UPCH had 10,7 ± 2,41 [95 % CI (10,08-11,39)]; p=0.002. Conclusions: The level of knowledge about antibiotic prophylaxis of infective endocarditis in last- year dental students in Lima is predominantly low.