Objective To investigate the effect of ultrasound guided paravertebral catheterization paravertebral block (CTPB) and patient-controlled intravenous analgesia (PCIA) on postoperative analgesia and pulmonary function in patients with multiple rib fractures.Methods Totally 46 cases of trauma patients with multiple rib fractures who underwent internal fixation admitted to Yichang Central People′s Hospital from Jan. 2020 to Jan. 2022 were included in this study. All patients were underwent internal fixation during hospitalization. Among them, 46 patients were divided into CTPB group (n=23) and PCIA group (n=23) using random number table method. In PCIA group, sufentanil+flurbiprofen axetil were used for intravenous analgesia. In the CTPB group, a suitable ultrasound guided catheter was placed for continuous thoracic paravertebral intercostal nerve block with ropivacaine after operation. All patients were observed until the 3rd day after operation. Chest wall pain VAS score in the resting/cough state, arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), Before the operation (T0), at 3h (T1), 1 day (T2), 2 days (T3), 3 days (T4) after analgesia, arterial blood samples were collected to lest the levels of Pa02, PaC02 and Pa02/FiO2. The pulmonary function was also examined before (T0) and 3 days (T4) after the operation through FEV1 and FEV1 %. Results CTPB group compared with the PCIA group at T 1, T 2, T 3 and T 4 after analgesia, the level of resting and coughing VAS were significantly decreased (P<0.05), the level of PaO2 and PaO2/FiO2 were increased （P<0.05）, and FEV1, FEV1% were increased (P<0.05) at 3 d after analgesia. Conclusion Compared with the PCIA, CTPB improves the arterial oxygenation function and accelerates the recovery of pulmonary function in patients with multiple rib fractures after internal fixation operation