Background: Understanding syndemic effects of COVID-19 and HIV/AIDS can inform future public health preparedness. This study quantifies the all-cause excess death rate of people living with HIV/AIDS (PWHA) during the 2020-2022 COVID-19 pandemic in the United States (U.S.), including stratifications by sex, age, race/ethnicity, and region. Methods: Using publicly available data from the CDC AtlasPlus dashboard, we employed ensemble n-subepidemic modeling framework (SubEpiPredict toolbox). This dynamic parametric approach is well suited for counterfactual forecasting with relatively short time series and was used to generate expected deaths among PWHA for 2020–2022 based on pre-pandemic trends. The models were calibrated using 12 years of pre-pandemic mortality trends (2008-2019), with the median excess death rate calculated as the difference between forecasted and observed death rates. Results: Overall excess mortality among PWHA was estimated at 7,783 crude excess deaths (95% prediction interval [PI]:5,098–10,525), corresponding to 2.77 excess deaths per 100,000 people (95% PI:1.81–3.75), with the largest burden observed in 2021. Excess death rates were highest among male (3.39), age 55–64 (4.94), multiracial (12.82), and Northeast (4.12) groups. The largest crude number of excess deaths occurred among male (4,692), age 65 + (2,560), Black/African American (3,969), and Southern (4,025) groups. Conclusions: These systematic, model-based results reveal stark heterogeneities among PWHA by exposing recent mortality patterns that may not be captured by disease-specific mortality reporting alone. These findings provide a robust, reproducible benchmark for assessing pandemic-related disparities and can inform future public health resource allocation and tailored interventions for vulnerable populations.