Cancer remains a growing public health challenge in Tanzania and across sub-Saharan Africa, where limited access to conventional chemotherapy and high treatment costs continue to drive reliance on medicinal plants as therapeutic alternatives. Tanzania harbors exceptional floristic diversity and a long-documented tradition of ethnomedical cancer treatment, yet the systematic isolation, structural characterization, and pharmacological validation of anticancer bioactive compounds from its flora remain comparatively underdeveloped relative to neighboring East African countries. This review synthesizes current knowledge on medicinal plants traditionally used for cancer management in Tanzania, the extraction and chromatographic isolation techniques applied to recover their bioactive constituents, the spectroscopic and spectrometric methods used for structural elucidation, and the in vitro and in vivo evidence supporting their anticancer activity. Particular attention is given to terpenoids, flavonoids, and alkaloids as the dominant classes of cytotoxic phytochemicals reported from East African flora, and to the structure-activity relationships that underpin their mechanisms of action. The review further identifies methodological, regulatory, and conservation-related challenges that constrain translation of ethnobotanical leads into validated drug candidates, and proposes priorities for future research, including bioassay-guided fractionation, dereplication-based metabolomics, and strengthened intellectual property and benefit-sharing frameworks. Collectively, the evidence indicates that Tanzanian medicinal plants represent an underexploited reservoir for anticancer drug discovery that merits coordinated, multidisciplinary investigation.