The methods of reduction of depressed posterolateral fragments in tibial plateau fracture through anterolateral approaches remain controversial. This paper aimed to compare the intraarticular osteotomy technique and the "window" osteotomy technique for the reduction of depressed posterolateral fragments through anterolateral approach.From January 2015 to January 2022, we retrospectively reviewed the data on patients with tibial plateau fracture involving depressed posterolateral fragments treated with the intraarticular osteotomy or the "window" osteotomy. 40 patients underwent the intraarticular osteotomy were divided into group A, while 36 patients underwent the "window" osteotomy were divided into group B. The operative time, bone grafting volume, fracture healing time, complication, reduction quality and postoperative functional results were compared between the two groups.The average follow-up duration was 16.6 ± 3.7 months. The average bone grafting volume for all patients in group B was essential larger than group A (p = 0.001). Compared to group B, patients in groups A had significantly shorter fracture healing time (p = 0.011). The depth of depressed articular surface, PSA and the radiographic evaluation at 2 days and 6 months after surgery in group A were significantly lower than group B (p<0.05). Based on the HSS knee-rating score, no significant difference in function results was found between the two groups (p>0.05). No significant difference was found in operation time and blood loss between the two groups (p>0.05).The intraarticular osteotomy could obtain satisfactory clinical results in tibial plateau fracture involving posterolateral fragments.© 2023. BioMed Central Ltd., part of Springer Nature.