Those facts I have studied on the theoretical characteristics of stock price earning ratio related with firm evaluation are as followings. First, I have investigated stock valuation analysis under certainty in view of Miller's, Modigliani's and Linter's theories in Chapter Ⅱ, and it is found that stock valuation under uncertainty to which the basic model of MM theory and the concept of capitalization ratio are applied is the same output, as in the case under certainty. And I have examined the stock valuation of growth corporations in which net investment, total capitals and operating profits are expected. Second, I have reexamined the fact that stock price profits are the erotical indices of firm valuation and the firm valuation on the basis of stock price earning ratio in Chapter III. As a whole, I have surveyed the stock price earning ratio theory of the growth stocks and there have been found some problems as such scholars as Malkiel and others have suggested focusing on the stock price structure of growth stocks. To conclude, there must be incessant efforts for the study of security analysis to make it develop ideally.