The latest researchs show that students have their own preconceptions about scientific phenomena or theory before they learn about it in school. The preconception exert a great influence on floe teaching and learning science. The purpose of this study is to find out the effect of intelligence and attitude to science on elementary school student`s scientific conception. For this study. 200 elementary school students were sampled from 4th and 6th grade. .Data were obtained by IQ test and the questionnaires on scientific conception and attitude toward science. The result was analyzed by t-test, Correlation and ANOVA in the statistical packages SPSS/PC^+. The major findings of this story are as follows: 1. The mean score of scientific conception of elementary school students was 12.89. The mean score of attitude to science was 247.29. The mean scare of intelligence was 109.93. 2. The correlation coefficient between scientific conception arid intelligence (r=.5098) was relatively high (p$lt;.001). The correlation coefficient between attitude to science and scientific, conception (r=.2364) was low (p$lt;.001). 3. Significant difference on science conception was found among grade levels (p$lt;.00l). Significant difference on science conception was not found between sex (p$gt;.05). 4. The subjects were divided into 4 groups by intelligence and attitude toward science. These 4 groups show the significant difference (p$lt;.01) in the scientific conception. The groups of high intelligence showed high scientific conception.