Objective: To explore the efficacy of ornidazole injection combined with latamoxef sodium in the treatment of pelvic inflammatory disease and its effect on serum inflammatory factors. Methods: A total of 97 patients with pelvic inflammatory disease admitted to Xiamen Fifth Hospital from June 2020 to May 2023 were randomly (random number table method) divided into control group (n=49) and observation group (n=48). The control group was treated with intravenous drip of latamoxef sodium, and the observation group was treated with intravenous drip of ornidazole + latamoxef sodium. The clinical efficacy, clinical symptom scores, pelvic effusion, inflammatory mass diameter and serum inflammatory factors [C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin (PCT)] levels before and after treatment were compared between the two groups. Results: The total effective rate of the observation group was higher than that of the control group (93.75% vs 77.55%, P<0.05). Compared with the control group, the clinical symptom score and serum CRP, IL-6, PCT levels were lower in the observation group after treatment, and the pelvic effusion volume and inflammatory mass diameter were smaller (P<0.05). There was no significant difference in the total incidence of adverse reactions between the two groups (8.33% vs 6.12%, P>0.05). Conclusion: The combined use of ornidazole injection can significantly improve the efficacy of latamoxef sodium alone in the treatment of pelvic inflammatory disease, improve clinical symptoms and signs, and reduce the level of serum inflammatory factors.