At this time the development of the restaurant business in Semarang so rapidly. The restaurant business developments create new players emerge, including from the students themselves. House of Moo is a dairy restaurant which located in the area Tembalang. Due to the many new players, companies need to examine existing consumer behavior and the factors that influence purchase decisions in marketing a product. This research was conducted explanatory causal quantitatively. Causal quantitative methods, is also a character study can be calculated numbers with statistical methods. The results showed that all variable marketing mix (7P) have positive effect on consumer purchasing decisions in the House of Moo, but there is one variable that does not significantly influence the purchasing decision. the variable is the process variable. While the variables that have the greatest influence on consumer purchasing decisions is physical evidence variable. This can result from data processing where the value t and the coefficient of determination of these variables have the greatest value of other variables