Osteoarthritis is a progressive disease causing pain and structural and functional changes in the affected joints. The increasing incidence of the disease is associated with society aging and the obesity epidemic. This progressing chronic disease causes disability and loss of independence. Treatment of this disease is focused on pain relief and includes treatment with non-steroidal anti-inflammatory drugs, diet supplements with glucosamine, chondroitin, and injections of hyaluronic acid into the affected joint. A very important part of treatment is physiotherapy as well as non-pharmacological treatment including patient education, body weight reduction, use of orthopedic equipment facilitating motility and kinesitherapy. The article is a review of the osteoarthritis literature, the disease pathophysiology and the ways of treatment.