Objective　To explore the effectiveness of internal fixations for complicated tibial plateau fractures using digital design and three-dimensional printing technique. 　Methods　A retrospective analysis was performed on 40 cases of complicated tibial plateau fractures at our department from October 2013 to September 2015．There were 27 male and 13 female patients．According to the Schatzker classification, there were 19 cases of typeⅣ，15 cases typeⅤ，and 6 cases typeⅥ．Among them, 20 patients (3D group)underwent 3D printing assisted operations for the following procedure: first construct 3D models, followed by virtual fractures reductions for choice of the most appropriate plates and printing of real-size 3D models; Afterwards, the fractures reduction was simulated with prebent plates, and 20 patients (control group) underwent conventional open reduction and internal fixation operations. The operation time, intraoperative bleeding, and incision length in 3D group, and knee functional scores were compared between the two group．Results　All 40 patients were significantly less than those in the control group (P<0.01). Allpatients achieved bony union after follow-up 8~13 months (mean, 10 months). The Rasmussen scores in 3D group were higher than those in the control group (P<0.01).　Conclusion　By using digital design software and three-dimensional (3D) printing technique, we can achieve individualized operation and precise treatment, which can lead to less blood loss and shorter hospital stay.