Purpose – to describe the relationship of selected socio-demographic, clinical, and surgical factors with the severity and patterns of postoperative pain during the first three days following total knee arthroplasty.Material and methods. The sample included 100 patients (93 women and 7 men; mean age 63.5±7.8 years) with osteoarthritis admitted for primary total knee arthroplasty. Prior to surgery, standard measures were used to assess preoperative pain and other symptoms, clinical manifestations of osteoarthritis, functional status of the knee, comorbidities, functional abilities, quality of life, and other patient characteristics. Physical, biochemical and surgical parameters of the perioperative period were also recorded. Patterns of daily changes in postoperative pain characteristics were investigated with the use of individual diaries. Results. All the analyzed indicators of postoperative pain progressively decreased during the three days after surgery (р0,001), including the number of daily hours of moderate to severe pain (р0,001). Pain levels were generally higher among women than among men (р = 0,009). Of the analyzed preoperative factors, higher levels postoperative pain were correlated with higher levels of anxiety (р = 0,029) and preoperative pain intensity (р = 0,029). Among the perioperative factors, surgery duration longer than 90 minutes was associated with higher levels of postoperative pain in activity (р = 0,012) and more hours of moderate/severe pain (р = 0,008). Characteristics of postoperative pain were unrelated to level of patient education, social or family status, employment, lifestyle, or any other clinical or laboratory variables.Conclusion. Of the many factors previously associated with postoperative pain, only gender, anxiety and level of preoperative pain confirmed their importance in this study. Among the perioperative factors, surgery duration, which varied by the type of implant, was significantly associated with postoperative pain levels.