This volume contains selected papers presented at the Fourth Asian Symposium on Computer Mathematics. There are 39 peer-reviewed contributions together with full papers and extended abstracts by the four invited speakers, G.H. Gonnet, D. Lazard, W. McCune and W.-T. Wu, and these cover some of the most significant advances in computer mathematics, including algebraic, symbolic, numeric and geometric computation, automated mathematical reasoning, mathematical software, and computer-aided geometric design.