Hepatitis B is a major public health problem in Senegal. This study aimed to evaluate the diagnostic performance and operational characteristics of the One step HBV (Blue CROSS Bio-medical Co.Ltd.) rapid test for the detection of HBV serological markers at the Dalal Jamm National Hospital Center (CHNDJ). An experimental study was conducted from April to June 2025 on 190 serum samples characterized by the ARCHITECT reference test. The test showed 100% specificity for HBsAg, anti-HBs, and anti-HBc. Sensitivity for HBsAg was 96.2% (Discordance Rate (DR): 2.1%), but was low for anti-HBs (50.9%, DR: 23.2%) and anti-HBc (58.3%, DR: 32.6%). The WHO operational score was 25/30, classifying the test as "Highly appropriate". In conclusion, the One step HBV (Blue CROSS Bio-medical Co.Ltd.) test is highly practical but has insufficient sensitivity for HBsAg according to WHO standards (>99%) and is particularly low for anti-HBs and anti-HBc. Its use should be cautious, especially for markers other than HBsAg, to avoid false negatives.