On the basis of the obtained free cash flow of companies,the multiplier of free cash flow and the debt of free cash flow ratio were introduced. After integrating operating cash flow, market surplus ratio, market net ratio, low financial lever, the securities portfolio investment of correlation index were con structured. It was validated that the stock market would effect the ration of low market surplus, the ratio of low market net and the multiplier of low free cash flows. The yield ratio of portfolio investment could be improved evidently by introducing the multiplier of free cash flows.