Abstract: This study aimed to investigate the synergistic effect of lidamycin (LDM) and rituximab on human B cell lymphoma Ramos cells. Cell proliferation was measured using MTS assay, cell apoptosis was analyzed by Annexin V-FITC/PI assay, the expression of apoptosis related proteins was analyzed by Western blotting, and the in vivo lymphoma inhibition was verified using BALB/c mice inoculated via tail vein using Ramos cells which stably expressed pEGFP-N1 plasmid. The results showed that, after the pretreatment with rituximab for 48 h, rituximab and LDM showed significantly synergistic effects on cell proliferation. Cells in combined treatment group had a higher apoptosis rate than that in LDM treatment group. Compared with the LDM treatment group, the expression of apoptosis-related proteins such as Cleaved caspase-3, Cleaved caspase-7, Cleaved caspase-9 and Cleaved PARP in combined treatment groups increased, and expression of cIAP-2 and Bcl-2 decreased. The result of in vivo experiment showed that, in the combined treatment group, the survival time of BALB/c mice was significantly longer than the mice in control group and LDM treatment group, and the degree of tumor accumulation and metastasis to lymph nodes and spleen was lower.