The purpose of this study was to compare the logical thinking and language ability of preschool children who were provided with questioning experiences and of those who were provided with story-telling. Fifty of five to six years, preschool children of Prachuabkhirikhan kindergarten School of the 1993 academic year were rendomly sampled into two groups then randomly assigned into the experimental group which was provided with guestioning experiences and the control group which was provided with story-telling using the lesson plan by the Office of the National Primary Education Commission Logical thinking tests (of Piaget) developed by Duangduen Satraphat and Language Ability (narratation) test of Manvika Pholphirut. The Randomized control-groups pretest-posttest design was applied. The experimental period was 8 weeks. The findings were as follows : 1. The preschool childrens logical thinking through guestioning experiences inproved significantly at the .01 level. 2. The preschool childrens logical thinking through story-telling experiences improved significantly at the .05 level. 3. The preschool childrens language ability through questioning experiences improved significantly at the .01 level. 4. The preschool childrens language ability through story-telling experiences improved significantly at the .01 level. 5. The logical thinking of the children in the two groups was significantly different at the .01 level. The logical thinking of the preschool children who were provided with questioning experiences was higher than those of the preschool children who were provided with story-telling experience using the lesson plan by the Office of the National Primary Education Commission. 6. The language ability of the children in the two groups was significantly different at the .01 level. The language ability of the preschool children who were provided with questioning experiences were higher than those of the preschool children who were provided with story-telling experiences using the lesson plan by the Office of the National Primary Education Commission.