Objective To compare the effect of transabdominal approach and retroperitoneal approach laparoscopic partial nephrectomy (LPN) in the treatment of stage T1aN0M0 renal carcinoma, and to provide clinical reference. Methods The clinical data of 100 patients with T1aN0M0 renal carcinoma who underwent LPN in Xuzhou Cancer Hospital from January 2021 to January 2024 were retrospectively analyzed and divided into the control group (50 cases , LPN was treated by transabdominal approach) and the observation group (50 cases , LPN was treated by retroperitoneal approach) according to the different points of surgical method.The levels of perioperative indexes, stress response indexes and the occurrence of postoperative complications were compared between the two groups. Results The operation time and postoperative hospitalization time in the observation group were shorter than those in the control group (all P<0.05). There was no significant difference in the success rate of operation and the amount of blood loss during operation between the two groups (all P>0.05). On 1st day after surgery, the levels of malondialdehyde (MDA) and cortisol (Cor) in two groups were higher than before surgery, but the observation group was lower than control group (all P<0.05). There was no significant difference in the total incidence of postoperative complications between the two groups (P>0.05). Conclusion Compared with transabdominal approach LPN, retroperitoneal approach LPN has advantages in the treatment of stage T1aN0M0 renal carcinoma in terms of operation time, postoperative hospitalization time and stress response reduction, and is worthy of clinical application.