The main purposes of this study were to inquire into the effects of teaching of self-regulated learning and cognitive styles on learning achievement and attirude of science of elementary school students . Quasi-experimental design was used. Two classes of fifth-grade students from an elementary school in Kaohsiung County were randomly assigned to either the experimental or the control group. After the Science Achievement Test, the Scale of Attitude for Learning Science, and the Scale of Cognitive Styles were administered on the two groups, the self-regulated learning instructtion was implemented in the Science class of the experimental group, while the control group was taught in the general way. After 8 weeks of instruction, the posttest and delayed test of the Science Achievement Test and the Scale of Attitude for Learning Science were administered on the two groups. The major findings of the study were as follows. (1) The experimental group got higher score than the control group in the learning achievement of science. (2) The learning achievement of science of different cognitive styles were promoted on the experimental group. (3) A significant difference was found on the interaction between the two groups and cognitive styles in the posttest scores of the learning achievement of science. (4) The experimental group got higher score than the control group in the learning attitude of science. (5) No significant difference was found between different cognitive styles in the learning attitude of science. (6) No significant difference was found on the interaction between the two groups and cognitive styles in the learning attitude of science. Based on the findings, some suggestions for science teaching practice and future research were proposed.