Melanoma is a skin cancer that arises from melanocytes and can spread quickly to the other organs of the body, if not treated early. Generally, melanoma shows an inherent resistance to conventional therapies. In this regard, new potential drugs are being developed as possible treatments for melanoma. In this paper, we report the synthesis of a new decavanadate compound with organic molecules for a potential therapeutic application. The tetra-[methylimidazolium] dihydrogen decavanadate(V) salt (C₄H₇N₂)₄[H₂V₁₀O₂₈] is characterized by single-crystal X-ray diffraction, by FT-IR, UV–Vis and ⁵¹V NMR spectroscopy, as well as by thermal analysis (TGA and DSC). The compound crystallizes in the monoclinic centrosymmetric space group P2₁/c. Its formula unit consists of one dihydrogen decavanadate anion [H₂V₁₀O₂₈]⁴⁻ and four organic 4-methylimidazolium cations (C₄H₇N₂)⁺. Important intermolecular interactions are N-H···O and O-H···O hydrogen bonds and π-π stacking interactions between the organic cations, revealed by analysis of the Hirshfeld surface and its two-dimensional fingerprint plots. Interestingly, this compound inhibits the viability of IGR39 cells with IC₅₀ values of 14.65 μM and 4 μM after 24 h and 72 h of treatment, respectively. The analysis of its effect by flow cytometry using an Annexin V-FITC/IP cell labeling, showed that (C₄H₇N₂)₄H₂V₁₀O₂₈ compound induced IGR39 cell apoptosis and necrosis. Molecular docking studies performed against TNFR1 and GPR40, as putative targets, suggest that the (C₄H₇N₂)₄[H₂V₁₀O₂₈] compound may act as inhibitor of these proteins, known to be overexpressed in melanoma cells. Therefore, we could consider it as a new potential metallodrug against melanoma.