This study investigates the antitumor effects and functional mechanism of resveratrol-bovine serum albumin nanoparticles (RES-BSANP) on human primary ovarian carcinoma cells in nude mice. An implanted tumor model was established by injecting a suspension of the human primary ovarian cancer cell SKOV(3) into the subcutaneous tissue of nude mice. The tumor-bearing mice (n = 32) were randomly divided into 8 groups, which received intraperitoneal injections of normal saline (0.9%, 0.5 mL), BSA (1.5 mg/kg, 0.5 mL), or RES-BSANP or RES (200, 100, and 50 mg/kg, 0.5 mL), respectively, once a week for 4 weeks. The in vivo antitumor efficacy was evaluated by measurement of tumor volume, whereas morphological alterations were observed by transmission electron microscope (atomic force microscopy); TUNEL assays and immunoblotting for apoptotic and cell proliferation proteins were carried out to elucidate the possible mechanism. RES-BSANP was found to exhibit certain highly desirable characteristics such as innocuity, better dispersity, and water solubility; it affected the in vivo tissue/organ distribution of RES in a remarkable manner. The administration of RES-BSANP significantly retarded the growth of carcinomas in nude mice from the third week onwards, and the inhibition rate was markedly higher than in mice treated with RES (52.43% vs. 46.34%, p < 0.05), without causing weight loss (p > 0.05). Simultaneously, apoptotic and necrotic morphological characteristics were observed with electron microscopy in the tumor tissues of treated mice. TUNEL staining revealed that the tumors from RES-BSANP-treated mice exhibited a similar apoptotic index as RES control tumors. Western blot analysis of the protein expression profiles revealed that part of the mechanism may be mediated by triggering the release of cytochrome c from the intermembrane space and upregulating the expression of caspase-9 and caspase-3, suggesting that the mitochondrial apoptotic pathway was being activated.