Nanostructured silicon has been regarded as a promising next-generation anode material for high energy density lithium-ion batteries. However, costly synthesis methods and low initial coulombic efficiency are still two major challenges for its practical application. Herein, secondary submicron silicon materials composed of nanoparticles are successfully prepared by a simple, low-cost, and efficient high energy mechanical milling method. The initial coulombic efficiency of the as-prepared silicon anode reaches 89.14% with a first discharge specific capacity of 3233 mA h g–1 at 100 mA g–1. In light of a low-cost precursor, facile approach, and high initial coulombic efficiency, this work may provide guidance and enlightenment in synthesizing nanostructured silicon with a secondary structure as anode materials for lithium-ion batteries.