Cisplatin-based chemotherapy is the standard regimen for bladder cancer patients, but its effectiveness is limited by high toxicity and the development of drug resistance. It has been reported in many studies that Cucurbitacin B has anti-carcinogenic effects by stimulating apoptosis and autophagy. Here we explored the potential role of cucurbitacin B on MB49 bladder syngeneic mouse tumor model. Single and combined doses of cucurbitacin B and cisplatin were applied to MB49 cell line and the cell viability was determined by Water-Soluble Tetrazolium Salt-1 (WST) method. After developing the tumor model, mice were randomly divided into four groups and then cucurbitacin B and cisplatin applied in the specified doses and time. The expression levels of apoptosis (Bcl-2, Bax, Caspase-3, cleaved Caspase-3) and autophagy proteins (Beclin-1 and LC3I, LC3II) were detected by Western Blot. Phospho-protein array analysis was performed to determine the relative levels of phosphorylation of proteins which are associated with the PI3K-Akt signaling pathway. Tumor tissues were analyzed by hematoxylin-eosin staining. In the present study, the results showed that cucurbitacin B inhibited the expression of Bcl-2 and increased the expression of Bax and cleaved Caspase 3. LC3II is markedly up-regulated in cucurbitacin B-treated cells. Cucurbitacin B reduced the phosphorylation of p27, PRAS40, and Raf-1 proteins. CuB + Cis combination synergistically decreased phosphorylation of AKT, ERK1/ERK2, mTOR, BAD levels and increased the level of AMPK alpha. PI3K/AKT/ mTOR pathway might be one of the targets of cucurbitacin B in MB49 bladder cancer mouse model. CuB + Cis combination reduced the tumor growth. Cucurbitacin B has no toxic effects on lung, liver, kidney, heart, and bladder. Indeed, cucurbitacin B can inhibit the tumor proliferation; induce caspase-dependent/-independent apoptosis and autophagy. Our study provided a novel perspective to research the effects of cucurbitacin B on the apoptotic and autophagic pathways in bladder cancer and a new target class for drug development.