Introduction Nutritional management is a fundamental practice of concern to all patients infected with the human immunodeficiency virus (HIV). The nature of HIV/AIDS and malnutrition impacts are interlocked and intensify one another. Objective This study aimed to explore nutrition management challenges among people living with HIV on antiretroviral therapy (ART) in primary health centres in Addis Ababa, Ethiopia. Methods and materials We used a hermeneutic (interpretive) phenomenological study design. The study used in-depth interviews to describe lived experiences among adult patients aged 18 and above. We selected the participants purposively until the saturation of the idea reached. We maintained the scientific rigor and trustworthiness by applying credibility, transferability, dependability, and conformability, followed by translation and re-reading of the data has been achieved. The data have been analyzed through inductive thematic analysis assisted by NVIVO version 12 pro software. Result Nutrition management challenges for HIV patients have been described using six significant themes. The major themes were: acceptance of the disease and the health status; facilitators and barriers to treatment adherence; behavioural changes in eating patterns; experience of food insecurity issues; nutrition knowledge; and support. The themes have explained how patients using ART have been challenged to manage their nutrition ever since their diagnosis. Of all challenges, food insecurity is found to be the core reason for poor nutrition management. Conclusion and recommendation We found that many factors in managing their nutrition challenged patients with HIV. There should be an increasing interest in managing food insecurity issues as food insecurity has been strongly related to other factors.