Abstract. Suffix array is a data structure that can be used to index a large text file so that queries of its content can be answered quickly. Basically a suffix array is an array of all suffixes of the text in the lexicographic order. Whether or not a word occurs in the text can be answered in logarithmic time by binary search over the suffix array. In this work we present a method to compress a suffix array such that the search time remains logarithmic. Our experiments show that in some cases a suffix array can be compressed by our method such that the total space requirement is about half of the original.