Uganda applies the World Health Organization threshold of 1,000 copies/ml to determine HIV viral non-suppression. While there is an emerging concern of low-level viraemia (≥50 to <1,000 copies/ml), there is limited understanding of how people on antiretroviral therapy perceive viral load testing and low-level viremia in resource-limited settings. This qualitative study used the health belief model to explore the meaning that people living with HIV attach to viral load testing and low-level viraemia in Uganda. We used stratified purposive sampling to select people on antiretroviral therapy from eight high volume health facilities from the Central, Eastern, Northern and Western regions of Uganda. We used an interview guide, based on the health belief model, to conduct 32 in-depth interviews, which were audio-recorded and transcribed verbatim. Thematic analysis technique was used to analyze the data with the help of ATLAS.ti 6. The descriptions of viral load testing used by the participants nearly matched the medical meaning, and many people living with HIV understood what viral load testing was. Perceived benefits for viral load testing were the ability to show; the amount of HIV in the body, how the people living with HIV take their drugs, whether the drugs are working, and also guide the next treatments steps for the patients. Participants reported HIV stigma, lack of transport, lack of awareness for viral load testing, delayed and missing viral load results and few health workers as the main barriers to viral load testing. On the contrary, most participants did not know what low-level viraemia meant, while several perceived it as having a reduced viral load that is suppressed. Many people living with HIV are unaware about low-level viraemia, and hence do not understand its associated risks. Likewise, some people living with HIV are still not aware about viral load testing. Lack of transport, HIV stigma and delayed viral load results are major barriers to viral load testing. Hence, there is an imminent need to institute more strategies to create awareness about both low-level viraemia and viral load testing, manage HIV related stigma, and improve turnaround time for viral load results.