Biologically active new organotin(IV) acetates (1-6) of p-tolyl acetic acid have been synthesized and characterized by multinuclear nuclear magnetic resonance ((1)H, (13)C) and mass spectrometry. The X-ray crystallographic data of compounds (3 and 4) were also collected. These studies show that in diorganotin(IV) compounds (compounds 1, 2, 3, and 6), tin exists in skew trapezoidal geometry with four strong and two weaker bonds, whereas triorganotin(IV) carboxylates (compounds 4 and 5) have four and five coordinated geometries in solution and solid form, respectively. These compounds were screened for a range of biological activities. Antibacterial activities were determined against six pathogenic bacterial strains, three Gram-positive and three Gram-negative; the activities were measured in terms of inhibition zones (mm). Antifungal activities were determined against six pathogenic fungal strains, cytotoxicity by the brine shrimp lethality assay, and antitumor activities by the crown gall tumor inhibition (potato disc) assay.