Objective To analyze the effect of scalp nerve block with 0.5% ropivacaine on postoperative inflammatory factors, hemodynamics and analgesia in patients with craniotomy. Methods 96 patients who needed craniotomy in our hospital from January 2019 to January 2021 were selected as the research objects. According to the difference of anesthesia, they were divided into local infiltration anesthesia group (group A) and scalp nerve block with 0.5% ropivacaine group (group B), with 48 cases in each group. In group A, 15mL 0.5% ropivacaine was used for infiltrate anesthesia along the surgical incision before the incision of skin. Group B was given 0.5% scalp nerve block. The scalp nerve block was located at the bilateral supraorbital nerve, auriculotemporal nerve, supratrochlear nerve, lesser occipital nerve, and greater occipital nerve as needle entry points. The skin was routinely disinfected, and 1 mL 0.5% ropivacaine was injected at each needle point. After the operation was completed, combined intravenous-inhalation anesthesia is used for maintenance. The levels of inflammatory factors ［C-reactive protein (CRP), interleukin-6 (IL-6), interleukin- 10 (Interleukin-10, IL-10)］ in the two groups were compared before surgery and 6h, 24h, 48h, 72h after surgery. The hemodynamics of patients ［Mean arterial pressure (MAP) ), Heart rate (HR)］ between the two groups were compared before induction (T0), immediately when incising the skin(T1), during craniotomy (T2) and sutured. The patients' pain 2h, 4h, 8h, 12h, 48h after the operation between the two groups were compared ［Visual Analogue Scale (VAS)］. The postoperative adverse reactions (fever, nausea and vomiting, dizziness) between the two groups were compared. Results There were no significant differences in the levels of inflammatory factors between the two groups before surgery (P＞0.05). The levels of CRP and IL-6 in the two groups significantly increased 6h and 24h after surgery, and the level of IL-10 was significantly reduced. The level of CRP and IL-6 gradually decreased after 48h, and the level of IL-10 gradually increased. After 72h, it was the same as that before the operation, especially in patients in group B (P＜0.05). There was no significant difference between the two groups at T0 (P＞0.05). The MAP and HR levels of the two groups at T1~T3 were higher than those at T0, but the MAP and HR levels of group B at T1~T3 were significantly lower those in group A (P＜0.05). The postoperative VAS score showed a downward trend. The VAS score of group B was significantly lower than that of group A at all time points after surgery (P＜0.05). The total incidence of adverse reactions in group B was significantly lower than that in group A (P＜0.05). Conclusion The scalp nerve block with 0.5% ropivacaine can significantly inhibit the inflammatory response of craniotomy, improve the patient's hemodynamics, and relieve postoperative pain, and it has high safety.