BACKGROUND: HIV positive women are at a risk of transmitting HIV to their children through unintended pregnancies and to their partners. A way of preventing this, is through the use of modern contraceptives. There have been cases where women use contraceptives and some don’t use at all due to some factors such as limited access, lack of awareness, cultural and religious opposition, poor quality of available services, gender based barriers and spousal disapproval but there is limited data. This study aimed to determine contraceptive use among HIV infected women as one of the means to prevent unintended pregnancies and partner transmission. OBJECTIVES: To determine the prevalence and factors associated with contraceptive uptake among HIV infected women aged 18-49 attending infectious diseases clinic at KCMC. METHODOLOGY: A hospital based descriptive cross sectional study. All HIV infected women attending Infectious Diseases Clinic (IDC) at KCMC from May to June 2016 through questionnaire. Data processing and analysis was done using SPSS version20. Permission to conduct research was asked from Kilimanjaro Christian Medical University College and Infectious Disease Clinic. RESULTS: Out of 303 study participants, 179 women reported that they were currently on modern contraceptive use which resulted to a prevalence of 59.08%. 144(47.5%) were using Condoms followed by the ones who used Injectables 25(8.3%), Oral contraceptives 16 (5.3%), LARC (IUD and Implants) were used by 29(9.6%), Tubal ligation 10(3.2%) and none of their partners had done a vasectomy. Factors affecting contraceptive use were: 30.1% were not having partners, contraceptives side effects 17.9%, being widowed 9.8% , Belief that people still get unwanted pregnancies even after use of contraceptives 7%, desire for more children 7.1% and other factors 28.1% such as Belief barriers, Partner restriction, Poor availability, Poor quality of contraceptives, Lack of contraceptive knowledge and discordance. CONCLUSION: Modern contraceptives uptake has increased as compared to previous years. Condoms are still a method of preference because of being easy to use, accessibility and protection against unintended pregnancies and partner protection. Other methods such as LARC and female sterilization, though being effective are not used much by HIV positive women. Some factors that were a barrier to contraceptive use, are no longer affecting contraceptive use such as traditional and religious beliefs. This is an improvement especially in Tanzania.