Total knee arthroplasty (TKA) is a very successful procedure in alleviating pain and improving function in patients with gonarthrosis. The rate of complications are rising due to the higher number of operations and indications. Complications after primary TKA differ regarding the level of arthrosis in the operated knee, general health status of the patient, experience and talent of the operating surgeon, characteristics of the implant, surgical method, postoperative care and follow-up. Most of these complications are tolerated with conservative management but in some cases revision surgery is needed. Infection and instability are the two main complications requiring early revision surgery. However polyethylene wear and aseptic loosening are the two complications mostly requiring a revision surgery in the late postoperative period. Complications of TKA can be minimized with a proper patient selection, improvement of preoperative comorbidities, careful sterilization, appropriate surgical approach, adequate soft-tissue balance, correct implant alignment, restoration of joint line and close follow-up of patients.