BackgroundTo improve pregnancy outcomes, a pregnant mother living with HIV/AIDS requires a high level of social and emotional support. However, women from low-income countries were subjected to low social support status despite adequate counseling and health messages to increase their social support. Therefore, this study aimed to investigate the predictors of the perceived poor social support status among pregnant women attending ART clinics in Southwest Ethiopia. MethodsA hospital-based cross-sectional study with consecutive sampling was conducted to enroll 265 pregnant women on antiretroviral therapy (ART) from December 1 to 30, 2021. The data were collected using an interviewer-administered questionnaire. Epidata was used for data entry and analyzed after it was exported to a statistical package for the social sciences. Binary logistic regression was used and the level of significance was declared at P-value <0.05 using Adjusted odds ratio at 95% CI after candidate variables were identified in binary logistic regression at a P-value of <0.25. ResultsFinding from the study figured out that low level of poor social support is found to be 47.2%. Study revealed that income level[AOR = 5.1 95% CI [1.9,13.6]], disclosure status[AOR: 1.9 95% CI [1.1,3.3]], unwanted pregnancy [AOR = 2.3 CI; [ 1.4,3.9]], and low adherence level[AOR: 2.1 95% CI [1.1,3.1]] were strong predictors. ConclusionThis study identified high levels of poor social support. Increasing access to information education and communications focusing on stigma, disclosure & refresher training that boosts the counseling skills of health care providers to enhance adherence level is strongly recommended.