Paeoniflorin is a water-soluble monoterpenoid glycoside that can be derived from multiple herbaceous plants, such as Radix Paeoniae Rubra, Radix Paeoniae Alba, Paeonia suffruticosa and Cimicifugae Foetidae. Multiple studies have suggested that Paeoniflorin possesses an excellent anti-tumor effect in variety of tumors, including liver cancer, gastric cancer, breast cancer, lung cancer, pancreatic cancer, colorectal cancer and bladder cancer. It can induce cell apoptosis, inhibit proliferation, invasion and metastasis via different molecular mechanisms, which are mainly involved in nuclear transcription factor kappα (NF-κB), B-cell lymphoma-2(Bcl-2) family, MicroRNA, neural precursor cell expressed developmentally down-regulated protein 4(NEDD4) signaling pathway, transcription activating factor (STAT3), p21, p53/14–3–3 signaling pathway, transforming growth factor-β1(TGF-β1)/Smads signaling pathway, Mitogen-activated protein kinase (MAPK) signaling pathway and Notch-1. Current studies on anti-tumor effect and mechanism of action of Paeoniflorin remain unclear. Therefore, this study reviews the research progress in the anti-tumor effect and mechanism of Paeoniflorin in an attempt to provide a new thought and theoretical basis for further development and clinical application of Paeoniflorin.