Abstract: The mixture of Ti powder, Sn powder and C powder with mass ratio of 2:1:1 was mechanically alloyed in a simoloyer mill, and then was treated by aging at room temperature. The phase composition, microstructure and formation mechanism of Sn whiskers in the mechanical alloying powder were studied. The results show that flocs appeared in the power mixture after mechanical alloying and aging at room temperature, and were composed of Sn whiskers. The Sn whiskers were columnar, collicular-shaped or nodular, knotted or curved, and needle-shaped single crystal β-Sn with body centered tetragonal structure. The whisker had a diameter of about 100 nm, and the zone axis was011 zone axis of β-Sn. Under heat and huge stresses produced by mechanical alloying, the recrystallization and direct growth of Sn occurred, and then Sn whiskers were obtained.