Objective:To explore the safety and efficacy of laparoscopic non-blocking partial nephrectomy assisted by high power lateral green laser in the treatment of T 1a renal tumor. Methods:The clinical data of 10 patients with T1a stage renal tumor from February 2021 to April 2021 in department of urology, Gongli hospital affiliated to Naval Military Medical University were retrospectively analyzed. There were 7 males and 3 females, aged 47.0-74.0 years, with average of(58.8±9.7)years old. The diameter of the tumor ranged from 2.0 cm to 3.8 cm, with an average of (3.1±0.6)cm. There were 6 cases on the left side and 4 cases on the right side, locate on lumbar side in 9 cases and ventral sied in 1 case. The R. E.N.A.L score was 4.0-6.0, with an average of (5.0±0.8). The preoperative creatinine was 66.9-90.1μmol/L, with an average of (75.1±9.0)μmol/L, preoperative GFR of 44. 6- 67. 3 ml /min, with an average of(56.7±7.7)ml/min, preoperative hemoglobin level of 119.0-156.0g/L, with an average of (135.8±11.4)g/L. All patients underwent laparoscopic non-blocking partial nephrectomy assisted by 180w lateral green laser, free the surrounding area of the tumor fully and completely expose the renal tumor. The laser fiber was placed through the green laser hand piece, and the fiber was connected with normal saline to wash the strip. The initial green laser vaporization power was set at 80W, and the hemostasis power at 35W.About 3mm away from the edge of the tumor, and one optical fiber away from the renal parenchyma, the renal parenchyma was cut with 80W power. In order to reduce the interference by smoke, high-pressure flushing was used through the optical fiber while vaporizing, and an attractor was used to push and peel the tumor. In case of bleeding during operation, hemostatic power can be used to close the bleeding point and gradually advance until the tumor was completely removed. The wounds of renal inner medulla and renal outer cortex were continuously sutured in 1-3 layers with barbed suture. It involved 9 cases via retroperitoneal approach and 1 case via abdominal approach. The operation time, postoperative hemoglobin decrease, extraction time of negative pressure drainage, postoperative hospital stay, postoperative pathology and postoperative complications were recorded, and the serum creatinine level and GFR level of the affected side were followed up 1 month after operation.Results:All the operations were successfully completed, and there was no conversion to open surgery or radical nephrectomy. One case changed to scissors fast resection and sutured hemostasis due to severe intraoperative bleeding. The operation time was 90.0-120.0 min, with the average of (104.5±9.0)min. The postoperative hemoglobin level was 96.0-132.0g/L, with an average of (115.2±11.8)g/L, and the difference was statistically significant ( P<0.05). The postoperative hemoglobin decreased from 12.0g/L to 25.0g/L, with an average of (20.6±4.6)g/L. The time of vacuum drainage was 5.0-7.0 days, with an average of (5.7±0.7)d. Postoperative hospital stay was 6.0-8.0 days, with an average of (6.7±0.7)d. No bleeding, urinary leakage and other complications occurred in all patients. There were 7 cases of clear cell carcinoma, 2 cases of papillary renal cell carcinoma and 1 case of angiomyolipoma. All margins were negative. One month after operation, creatinine ranged from 66.0 to 90.4μmol/L, with an average of (76.8±8.3)μmol/L, which was not significantly different compared with that before operation ( P>0.05). One month after operation, GFR was 45.1-60.8 ml/min, and with an average of (55.5±4.7)ml/min, and there was no significant difference compared with preoperative data( P>0.05). Conclusions:For T 1aN 0M 0 stage and exophytic renal tumors, laparoscopic non-blocking partial nephrectomy assisted by lateral green laser is safe and effective.