Trimethyltin(IV) complex containing the carboxylate ligand 2,3-methylenedioxybenzoic acid (HL) have been synthesized and characterized in solution state by multinuclear NMR (H-1, C-13 and Sn-119) using the noncoordinating solvent and also in solid sate by FTIR, mass spectrometry, and X-ray crystallography. Spectroscopic data have shown that methylenedioxy moiety has not coordinated with tin atom; instead, the coordination site is a -COO group, which is proved by spectral and XRD data. The solid state structure shows the trigonal bipyramidal geometry with a space group P2(1)/c. This compound was tested for its in vitro antitumor activity.