Total paravertebral block is a common analgesic and anesthetic technique that used in mastectomy procedures. In this study we aim to show the effects of ultrasound guided paravertebral block administiration on introperative opioid consumption and postoperative pain in modified radical mastectomy procedures. Nineteen patients that underwent thoracal paravertebral block with a diagnosis of modified radical mastectomy between 2017-2018 years were analysed retrospectively. Demographical parameters, procedure duration, intraoperative and postoperative 24 hours analgesic consumption were analysed. Statistical evaluation were performed with SPSS for Windows 21.0 programme. P<0.05 value was identified as statistical significance. Patients ages were between the range of 20-79 years and age avarage was 50,89 (±15,74). Three patients were ASA I, 6 patients were ASA II and 10 patients were ASA III. Body Mass Index avarage was 29,92(±3,99). Procedure duration avarage was 129,05(±66,04) minutes. Patients were divided into two goups; Group 1 (n=10): TPVB was not applied, Group 2 (n=9): TPVB was applied. There were no significant difference between groups in means of age and procedure duration. All patients in group 1 required opioid medication. Two patients required remifentanyl infusion, 4 patients required 100 µg and 4 patients required 150 µg intravenous fentanyl. None of the patients in Group 2 required opioid medication and this condition found statistically significant (p<0.005). All patients in Group 1 required postoperative analgesic treatment. Five patients had given contramal 60 µg 3*1, 5 patients had given contramal 60 µg 4*1. There were no postoperative analgesic requirement in Group 2 and it was statistically significant (p<0.005). Ultrasound guided thoracal paravertebral block in modified radical mastectomy provides an opioid free intraoperative period and obtain analgesia for postoperative 24 hours.