OBJECTIVE: Demonstrate the protective effect of hepatitis B in vaccine vulnerable health sciences students, under 30 years with three schemes the vaccination, two of them are conventional three doses and another one with two doses. HYPOTHESIS: Three schedules of vaccination dosage schemes hepatitis B produce antibody response over 10 IU/ml. DESIGN: Analytical, experimental, longitudinal., prospective and concurrent cohort study. MATERIALS AND METHOD: 100 vulnerable female and male students of the Medical Technology Faculty of the UNMSM Medical School were enrolled at first. 89 students completed the final analysis due to the inclusion and exclusion criteria in accordance with the study purpose. A vaccine dosage of 20 ug of surface antigen in 1 mL through three dosage schemes was administered: month 0, 1, 6; month 0, 1, 2; and month 0, 1. Blood samples were taken before and 1, 2, 6, and 7 months after the first dosage administration to determine the anti-HBs level. Anti-HBs approximately 10 mIU/mL was defined as seroprotective value. RESULTS: 89 students under 30 years (average age: 23.5 years). 46 (51.7%) male individuals, and 43 (48.3%) female individuals.12.4% of students reached protection within 30 days from the first dosage; 98.8% reached protection within 30 days from the second dosage; and 100% reached protection 180 days later. After the second dosage, the three groups reached protection values, and at the end of the study, the average antibody levels were between 532.7 mIU/mL and 1237.2 mIU/mL. CONCLUSIONS: This study showed an equivalent protective effect 7 months after the first dosage. An equivalent protective effect for hepatitis B was reached through three different vaccination schemes: conventional three dose scheme (month 0, 1, 6); two dose brief scheme (month 0, 1); and three dose brief scheme (month 0, 1, 2). A two dose scheme is suggested for individuals under 30 years, which would imply a higher compliance rate, lower cost, and a similar protection benefit.