Background: The prevalence of hypertension (HTN) among people living with HIV (PLHIV) has increased over the last decade globally. Given the dual burden of disease and significant prior investment in HIV care, integrating care for HTN and HIV is recommended. However, data on HTN screening, treatment, and control prior to such integration are lacking.  Using a mixed-methods approach, we assessed the baseline status of HTN screening, treatment, and control in 52 Ugandan public health facilities, participating in an ongoing cluster randomised trial of an integrated HIV/HTN care model. Methods: From November 2020 to March 2021, we reviewed patient records and randomly sampled 50 PLHIV without a documented HTN diagnosis per health facility and all PLHIV with a documented HTN diagnosis per health facility. We surveyed the sampled participants, took their blood pressure measurements, and described the HTN care cascade. We also conducted in-depth interviews with 24 patients and 12 providers to explore their experience with HTN screening and care. We used an in-depth thematic approach to analyze the resulting qualitative data. Results:  Among 2,645 PLHIV, <1% (20/2,645) reported having their BP measured within 6 months before the survey. The prevalence of HTN was 13.6% (359/2,645), including 287 (10.5%) newly diagnoses and 32 (1.2%) prior diagnoses that were not documented in their health record. Of 49 (1.9%) with a previously documented HTN diagnosis, 31 (63%) were on HTN treatment, and 53% had controlled HTN. In-depth interviews with providers and patients revealed a lack of blood pressure equipment, high patient load, limited technical HTN knowledge, and patients' fear of anticipated long waiting times as reasons for low HTN screening in the HIV clinics.  Conclusion: Regular screening for the detection of HTN patients was hardly performed. There is an urgent need for interventions to advance the integration of HTN care in HIV clinics.