Four-year-old and 5-year-old children and college students were assigned to positive information (PI) or negative information (NI) conditions. The PI group was given the story including positive event (Tomoko helped her mother with the table and was given a candy) and NI group was given the story including negative event (Tomoko helped her mother preparing the table, but she was not given a candy). Immediately after listening to the story, children were given the reasoning test in which they were required to solve whether statements were reasonable or not. Statements were constructed based on the combination of extent of generalization of actor (moderate generalization, over-generalization) together with three abstructionlevels of action. The main findings were as follows: (1) 4- and 5-year-olds judged over-generalization statements as reasonable but college students did not; (2) in NI condition, 4- and 5-year-olds judged higher abstract level statements as unreasonable while college students did not. These results were interpreted as indicating that preschoolers tend to over generalize actor's information, and can't generalize moderately negative information of action.