Background: Nationally representative as well as comparative studies had never been done in three West African countries: Ivory Coast, Cameroon and Gabon. Hence, this study focuses on comparison of HIV/AIDS related knowledge and acceptance attitude towards people living with HIV/AIDS (PLHA) of female youth among the three highly prevalent West African countries. Methods: The study utilized nationally representative datasets from Demographic and Health Surveys (DHS) of Ivory Coast 2011/12, Cameroon 2011, and Gabon 2012. IBM SPSS 22 was used to run multivariate logistic regression to find out the associates of HIV/AIDS related knowledge and attitudes as well as comparison among the countries. Results: There was lack of comprehensive HIV/AIDS knowledge and acceptance attitude towards people living with HIV/AIDS in the three countries. Age, residence (except Cameroon), educational level, religion (only in Ivory Coast), marital status and wealth index (except Ivory Coast) were significant associates of comprehensive HIV/AIDS knowledge. On the other hand, age (except Gabon), residence (only in Ivory Coast), educational level (except Gabon), religion (only in Cameroon), wealth index and comprehensive HIV/AIDS knowledge showed significant associations with acceptance attitude towards people living with HIV/AIDS. Higher comprehensive HIV/AIDS knowledge was detected among youth in Gabon (AOR=2.08, p<0.001) and Cameroon (AOR=2.06, p<0 .001) than in Ivory Coast. Results of acceptance attitude were in reverse manner to knowledge where less acceptance attitude was detected in Gabon (AOR=0.89, p=0.023) and Cameroon (AOR=0.86, p=0.003) than in Ivory Coast. However, comprehensive knowledge and acceptance attitude in Cameroon did not differ significantly from that of Gabon. Conclusion: Generally, very low comprehensive HIV/AIDS knowledge and acceptance attitude towards PLHA were observed in the three countries and specifically in Ivory Coast. At this instant, it is urgent to give emphasis on education to adolescents and rural residents. A need to convey information in a manner that is contextually appropriate, socio-culturally acceptable and gender-sensitive is suggested.