Abstract: The cost effective potassium titanate whiskers are artificial fibers with high performance. In this paper, their characteristics and properties, state of the art and method of preparation were reviewed, and their applications in composite materials were introduced in details. Also pointed out were some problems to be solved and the researching trend to follow. Studies of reducing the cost of whiskers, treating surface of whiskers and composing technology between whiskers and matrix are the most important topics in the near future.