Firstly, via comparing the features of intuitionistic fuzzy set(FS) and Pythagorean fuzzy set(PFS), three ranking methods for Pythagorean fuzzy numbers(PFNs) are analyzed, and some flaws of two ranking methods are pointed out. Then, it is illuminated that each PFN is characterized by four parameters, i.e., the membership degree, the nonmembership degree, the strength of commitment and the direction of strength. Simultaneously, the distance measures of PFSs and PFNs are investigated. The Hamming distance measure, the Euclidean distance measure and the Minkowski distance measure between PFSs and PFNs are proposed, and the desired properties are discussed. Finally, a multiple attribute decision making method in the Pythagorean fuzzy environment based on the proposed distance measures is presented. A numerical example is provided to illustrate the validity and applicability of the presented approach.