In order to study the effect of carrilizumab combined with cisplatin on apoptosis of esophageal squamous cell carcinoma cells Eca-109 by regulating mitochondrial oxidative phosphorylation (OXPHOS) and phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT) signaling pathway, and to observe the expression of heat shock protein A9 (HSPA9). In this study, the test was divided into blank control group, cisplatin group (100 μmol/L) and combined administration group which is cisplatin (100 μmol/L)+carrilizumab (200 mg/time). Transwell migration test, scratch test, cell counting kit 8 (CCK-8) test and clonal aggregation technique were used to observe the effects of carrellizumab combined with cisplatin on the invasion, migration and proliferation of esophageal squamous cell carcinoma cells Eca-109. The expression of HSPA9 gene was detected by RT-PCR. Western blot (WB) was used to detect the expression of OXPHOS and PI3K/AKT pathway proteins. Mitochondrial reactive oxygen species (ROS) were detected by flow cytometry. Transwell migration, scratch test, CCK-8 test and clonal formation test showed that the combined administration group inhibited the activity, migration and aggregation of Eca-109 cells more than the cisplatin group. Reverse transcription-polymerase chain reaction (RT-PCR) and WB detection results showed that compared with cisplatin group and control group, the expression of HSPA9 and OXPHOS in combined administration group significantly decreased, and the phosphorylation of PI3K/AKT was inhibited (P<0.01). Flow cytometry showed that compared with control group and cisplatin group, ROS levels in cisplatin+carrilizumab group significantly increased, and there was a significant difference (P<0.05). Compared with cisplatin alone, carrellizumab combined with cisplatin could significantly inhibit the expression of HSPA9 and OXPHOS in esophageal squamous cell cancer cells, inhibit the phosphorylation of PI3K/AKT signaling pathway, and regulate reoxidation and mitochondrial homeostasis. The inhibition of Eca-109 on esophageal squamous cell carcinoma by inducing mitochondrial apoptosis provides a reference for the precise intervention and treatment of esophageal squamous cell carcinoma in clinical practice.