The quality of veterinary medicinal products (VMP) is essential for efficient disease management. Therefore, VMPs that do not meet the required standards of quality can lead to increased sickness, death, and the development of antimicrobial resistance, posing a danger to both animals and humans. This study aimed to identify substandard and falsified VMPs on the Rwandan market using the Global Pharma Health Fund (GPHF)-Minilab™. VMP samples were purchased and collected in a cross-sectional study from veterinary retail pharmacies from five districts in four provinces of Rwanda, during May and June 2023. These samples were transported to the Veterinary Laboratory of the School of Animal Sciences and Veterinary Medicine, Nyagatare campus, University of Rwanda, and stored until analysis. The samples were subjected to physical and chemical analysis following the GPHF-Minilab™’s guidelines. A total of 130 samples from two categories of VMP were purchased from 10 veterinary retail pharmacies in urban and rural areas. The results of this study revealed that none of the assessed VMP samples failed physical tests (visual inspection, weight verification, and disintegration test). 10 samples (Sulfamethoxazole/Trimethoprim) out of 130 (7.7%) passed the visual inspections but later failed to comply with Thin-Layer Chromatography result specifications. This is an indication of the presence of substandard and falsified VMP circulating in Rwanda that warrants regular inspection and chemical quality control of VMPs along the supply chain.