OBJECTIVES: Adrenal vein sampling (AVS) is an established procedure for assessing subtype patients with primary aldosteronism (PA). However, it is technically challenging, with high failure rates, which limits its application in clinical practice. Our study aimed to evaluate the safety and efficacy of a single-catheter modified approach for AVS. METHODS: The clinical, angiographic, and procedural data of 182 consecutive patients who underwent AVS procedures between May 2020 and May 2023 were collected and analyzed. The single-catheter modified approach was performed as a single 5 F Tiger catheter with only one-time manual reshaping, which was recommended for sequential bilateral adrenal cannulations. RESULTS: Of the 182 consecutive patients, 174 (95.6%) had successful bilateral adrenal cannulation. The single-catheter modified approach was successfully performed to cannulate the right adrenal vein in 176 (96.7%) patients, while another six (3.3%) patients needed at least a second manual reshaping for 5 F Tiger catheters. For left adrenal cannulation, a single-catheter modified approach was successfully used in 179 (98.4%) patients, whereas 5 F Tiger catheters with at least second-time manual reshaping were used in the remaining three (1.6%) patients. The procedural period was 15.6 ± 10.8 min, the fluoroscopy time was 4.2 ± 1.5 min, and the diagnostic contrast was 15.5 ± 4.8 mL. The incidence of procedure-related complications associated with AVS was 1.1%. The cumulative summation assessment illustrated that the learning curve for the operating procedure required up to 29 cases, indicating that the procedure time was shortened after 29 cases. CONCLUSIONS: The single-catheter modified approach is an effective, safe, and feasible technique for AVS treatment. In particular, this improved method is not difficult for beginners with high technical success rates.