The objective of research was to understand the influence of Product Quality and World of Mouth on Purchasing Decision. Exogenous Variables were used in this research such as Product Quality and Word of Mouth, whereas Endogenous Variable was Purchasing Decision.Research type was explanatory with quantitative approach. This research was conducted in Surabaya (Tunjungan Plaza) especially at Charles & Keith Shoes Consumers. Sampling technique used The Equation of Machin and Campbell (1987:89). Result of this research indicated that R-square analysis was 0.529, meaning that 52.9% proportions of Purchasing Decision were influenced by independent variables of Product Quality and Word of Mouth. The influence of both variables was significant as proved by F-significance (0.000)