BackgroundFamily planning for HIV-positive women has numerous advantages. However, the need of family planning utilization is challenged by women’s nonautonomous decision-making power. Therefore, this study aimed to examine the level and associated factors of decision-making power to utilize family planning among HIV-positive married women.MethodsA facility-based cross-sectional study was conducted from March to June 2020 among 363 HIV-positive married women on ART, using systematic random sampling technique. Logistic regression analysis was used to identify variables that affect women’s decision-making power on family planning utilization. Statistical significance was declared at p-value < 0.05 with 95% confidence interval and strength of association was reported by adjusted odds ratio.ResultsOverall 55.2% (95% CI: 49.9–60.5) of the women had decision-making power on family planning utilization. Women’s having good knowledge (AOR: 2.87, 95% CI: 1.52–5.40), favorable attitude (AOR: 1.96, 95% CI: 1.13–3.38), women’s getting family planning counseling in ART clinics (AOR: 2.04, 95% CI: 1.16–3.59), women who get integration service of FP and ART (AOR: 1.83, 95% CI:1.07–3.12) were factors independently associated with women decision-making power on family planning utilization.ConclusionDecision-making power to utilize family planning among married HIV-positive women was low. Factors like poor knowledge about family planning, dissatisfaction with family planning service, not getting counseling about family planning in ART clinics, and not receiving family planning service in ART clinics were independently associated with women's decision-making power on family planning. Infrastructure linked with the health facility, knowledge, and attitudinal factors should all be combined in future family planning programs.