An etching composition for a semiconductor wafer is provided, including 0.5-50 wt % base, 10-80 wt % alcohol, 0.01-15 wt % additive and water. A method for etching a semiconductor wafer is also provided. When the etching composition is applied to the entire surface or a partial surface of the semiconductor wafer at 60-200° C., the etching composition reacts on the semiconductor wafer to form a foam that etches the semiconductor wafer and includes a solid, a liquid and a gas. At the same time, the additive forms an oxide mask on the surface of the semiconductor wafer. Therefore, an excellent texture structure is formed on the surface of the semiconductor wafer, and a single surface of the semiconductor wafer is etched.