Black single crystals of Ta(4)Se(9)l(8) are obtained in a high yield by heating Ta, Se, and l(2) at 300degreesC in 1:2.2:1.0 molar ratio. In the structure, the tantalum atoms form a square, with four Se-2 ligands bridging the Ta-Ta edges and one capping the square. Each Ta atom has two terminal iodine atoms. The compound is diamagnetic and has only two electrons for metal-metal bonding.