Objective： To explore the clinical efficacy of modified Dachaihu decoction with Sijin decoction in the conservative treatment of cholecystolithiasis with acute cholecystitis. Methods： One hundred and nine patients with cholecystolithiasis complicated with acute cholecystitis were classified into control group (n=54, routine treatment) and combined group (n=55, routine treatment plus modified Dachaihu decoction with Sijin decoction) based on treatment methods. The efficacy was assessed, and the TCM symptoms scores, pain degree and levels of C-reactive protein (CRP), interleukin-6 (IL-6) and interleukin-8 (IL-8) were compared between both groups, and the safety in the two groups was evaluated. Results： Compared with the control group, the clinical efficacy in the combined group was improved, and the TCM syndromes scores were decreased after treatment (P<0.05). The Visual Analogue Scale (VAS) scores in the combined group after 3 and 7 days of treatment were reduced compared to the control group (P<0.05). The combined group had decreased levels of CRP, IL-6 and IL-8 after treatment (P<0.05). No obvious difference between groups was exhibited in the occurrence of adverse reactions (P>0.05). Conclusion： Modified Dachaihu decoction with Sijin decoction has significant efficacy in the conservative treatment of cholecystolithiasis with acute cholecystitis, and it can effectively improve the clinical symptoms of patients, and relieve the pain and inflammatory response, with high safety.