Background: Adolescence is a challenging period in the life of every young person, more so for young girls, as they are more vulnerable to early unwanted pregnancies due to lack of adequate knowledge about protecting themselves when they have unprotected sexual intercourse and other romantic relationships with their partners. This study is carried out to determine the knowledge, attitude, and practices of contraception among senior secondary school girls of Banjul, The Gambia.
Method: A cross-sectional survey was conducted using semi-structured self-administered questionnaires among 307 participants aged 13-19 years from three senior secondary schools in Banjul. The data were entered into a computerised database and analysed using SPSS version 26. 
Results: The mean age of the participants was 17.9 years ± 1.2 years. All the participants knew the female sex organ, while only 98.7% knew the male sex organ correctly. Nearly all (99%) knew that pregnancy occurs due to unprotected sex, but only 15% knew that pregnancy is likely to occur in the middle of the menstrual cycle. Less than half (42.7%) agreed that contraception can prevent pregnancy. The majority of the participants (64.5%) were strongly against high school girls practicing contraception, and 34.9% believed that religion and culture have a negative impact on contraception practices. 
Conclusion: There is good knowledge of contraception within the young population, but its use is still low, and it could be due to socio-cultural factors.