The uncertainty of environment (the disaster of mud explosion of lapindo) and the society s willingness to be entrepreneurship thruogh small and medium business in Indonesia economy need the role of investment so that it is necessary to understand the factors influencing accounting information. This is true especially for the sake of decision making. The units analyzed of this research are accounting knowledge internal locus of control and uncertainty of the environment. Three propositions were developed to explain the results of this research. The research shows that the respondents used accounting knowledge as selling price to ensure that their products could be sold. Another finding is that it is found that the uncertainty of environment srongly affected toward using accounting information in decision making for investment.