Purpose: To evaluate the perioperative, functional and oncological results of retroperitoneal robotic-assisted laparoscopic partial nephrectomy (rRAPN) and transperitoneal robotic-assisted laparoscopic partial nephrectomy (tRAPN) for anterior renal masses. Methods: The charts of patients with anterior renal mass from February 2016 to December 2023 undergoing robotic-assisted laparoscopic partial nephrectomy (RAPN) were reviewed. Parameters including demographic characteristics, as well as perioperative, functional and oncological outcomes were analyzed. Univariable and multivariable logistic regression analyses were applied to explore the indicators for postoperative pentafecta achievement. Results: After propensity score matching, each group recruited 98 cases. Radius, Exophytic/endophytic, Nearness, Anterior/posterior, Location (R.E.N.A.L.) scores of all matched tumors were low or moderately complex (R.E.N.A.L. score <= 9). Demographic characteristics, histopathological data, perioperative and postoperative parameters were similar other than shorter operative time (OT; P = 0.018), less estimated blood loss (EBL; P = 0.031), earlier first anal exhaust (P < 0.001) and reduced postoperative length of stay (PLOS, P = 0.039) in the rRAPN group. With median follow-up durations of 55.2 months in the rRAPN group and 54.9 months in the tRAPN group (P = 0.711), no significant differences were observed in progression-free survival (P = 0.741), cancer-specific survival (P = 0.324), or overall survival (P = 0.549). Pentafecta achievement rates of rRAPN and tRAPN were similar and good (58.2% vs. 55.1%, P = 0.773). Multivariable analysis revealed that R.E.N.A.L. score (P = 0.002) but not surgical approach (P = 0.571) was the risk factor associated with pentafecta achievement. Conclusions: For anterior renal tumors of low or moderate complexity, both rRAPN and tRAPN provide robust and comparable results in terms of pentafecta achievement and oncological outcomes. The retroperitoneal approach offers shorter OT, less EBL, earlier first anal exhaust and reduced PLOS, which may suggest that rRAPN is an effective approach for selected anterior renal masses. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.