This research is to study the frequency of internet use in domestic trading companies and to analyze how to appear the effect of internet use in accordance with the frequency of internet use. The results of positive analysis are summarized as follows; First, the higher the frequency of internet use, the more likely buyer intimacy appears to be effective. Second, the higher the frequency of internet use, the more likely related companies or buyers are satisfied. Third, it is proved that an acquisition of marketing information is close relationship with internet use. That is, the higher the frequency of internet use, the more likely an acquisition on of marketing information is high. Ninth, the higher the frequency of internet use, the more likely the competitive predominance of companies is slightly enhanced.