The objective of this research is to study relation level between personal factor and mixing factor of the marketing and the decision- making to buy the portable computers of Krirk university students. The sample group is 351 Krirk university students. The research tool is the questionnaire. Data analysis is described as percentage value means standard deviation t-test and F-test. The results showed that personal factors including gender age level of education salary and influenced persons are related to the purchase of portable computers of Krirk university students at the 0.01 level. It was also found that mixing factors of marketing price place and marketing promotion has a statistically significant positive relationship with decision-making of the purchase of portable computers of Kirk university students at 0.01.