[Objective] To compare the clinical outcomes of total knee arthroplasty (TKA) assisted by computer assisted surgery (CAS) versus portable accelerometer-based navigation device (PAD). [Methods] A retrospective study was performed on 30 patients who under- went navigation-assisted TKA in our hospital from November 2018 to August 2021. According to doctor-patient communication, 12 patients had CAS used, while the remaining 18 patients had PAD applied. The documents of perioperative period, follow-up and imaging measur- ments were compared between the two groups. [Results] All the patients had TKA performed successfully with no significant differences in terms of operation time, cumulative blood loss on the third day after operation, and length of hospital stay between the two groups (P＞0.05). All of them in both groups were followed up for more than 12 months. Compared with that preoperatively, the VAS scores significantly de- creased (P＜0.05), while the HSS scores significantly increased at the latest follow-up in both groups (P＜0.05), which proved not significantly different between the two groups at any corresponding time points (P＞0.05). Radiographically, the hip-knee-ankle angle (HKAA) signifi- cantly decreased in CAS group and PAD group postoperatively compared with that preoperatively (P＜0.05). The preoperative and postopera- tive HKAA in both groups were not significantly different (P＞0.05). The mechanical medial proximal tibial angle (mMPTA) significantly in- creased in both groups postoperatively compared with that preoperatively (P＜0.05), which proved not significantly different between the two groups at any matching time points (P＞0.05). The mechanical lateral femoral angle (mLDFA) was significantly increased in the CAS group (P＜0.05), whereas which was of no change in the PAD group postoperatively compared with that preoperatively (P＞0.05). At any correspond- ing time points, there was no significant difference in mLDFA between the two groups (P＞0.05). [Conclusion] There were no significant dif- ferences between CAS and PAD used for assistance in TKA in terms of perioperative conditions, accuracy of lower extremity alignment and clinical efficacy. Therefore, both CAS and PAD can be selected flexibly according to the concrete situation.