Introduction: This study examined the factors related to the amount of blood loss and transfusion after primary total hip arthroplasty. Materials and methods: Sixty THRA patients, who had records of perioperative complete blood counts and transfusion, were enrolled in this study. Age, gender, diagnosis, use of cement, size of an incision, operative time, intraoperative crack, estimated blood loss, use of suction drain and the amount drained were used as possible variables. Results: The decrease in the serum hemoglobin level immediately after and 1 day after surgery was 3.18 and 3.90g/dL respectively. An average of 2.30 units were transfused in 78.3% of cases. The preoperative serum hemoglobin level, the use of a suction drain and the amount drained was related to the total amount of transfusion. Adverse transfusion reactions were found to be associated with the amount of transfusion Discussion: The reduction in the hemoglobin level and total amount of blood transfused showed no relationship with the variances associated with the surgical techniques. The total amount of blood transfused was significantly lower in the groups that had no suction drain. Therefore, a reduction in the volume of intraoperative transfusion and avoiding use of a suction drain can reduce the total amount of blood needed and reduce the adverse reactions of the transfusion.