Conventional total knee arthroplasty (TKA) has been developed for several decades. However, very few previous reports describe TKA with less invasive modality for extra-articular angular deformity. Herein, we report a case of navigation-assisted TKA for severe osteoarthritis associated with malunited distal femoral fracture. Fourteen months after navigation TKA surgery, satisfactory alignment, diminished length discrepancy, and improved range of motion were noted. Our report reveals that navigation system without intramedullary reaming is a feasible and less invasive alternative for TKA surgery for complex arthritic knee disorders.