The purpose of this research was to study and compare the skills of administrators in basic education schools in Rayong, Chanthaburi and Trat.Provinces in relation to the experience of the practitioners and the size of the school. The sample size of 361 administrators and teachers from basic education schools in Rayong, Chanthaburi and Trat Provinces was determined by Krejcie and Morgan is random stratified proportion method. The instrument for data collection was a five-rating scale questionnaire. The discrimination ranged from 0.21 to 0.44, and the reliability was at 0.82. The statistical analysis method used were : percentage, mean, standard deviation, t-test, one-way analysis of variance (One - way ANOVA) and Scheffes method was used to compare the pairs. The results showed that: 1) The skills of administrators from basic education schools in Rayong, Chanthaburi and Trat Provinces were at the high level, 2) The skills of administrators and teachers from basic education schools in Rayong, Chanthaburi and Trat Provinces, when compared by experience of practitioners, were not significantly different, 3) The skills of administrators from basic education schools in Rayong, Chanthaburi and Trat Provinces, when compared by school size, was significantly different overall and in each aspect at the .05 level.
