The purpose of this study were to introduce Assessment of Behavioral Componants(ABC) and to determine the effects of neurodevelopmental treatement on motro performance in 19 children with developmental disability. They were tested before and after the treatment period by ABC and assigned to early treatment group or delayed treatment group by the time at which treatment is initiated·. Analysis of the data was done by use of Wilcoxon signed rank test and Mann-Whitney. The results were as follows: 1. After the neurodevelopmental treatment the mean of ABC score was decreased to 19.36(p<0.01). 2. The mean of ABC score between before and after treatment was 18.28 for early treatment and 26.40 for delayed tratment group. The effects of NDT showed significant difference between before and after treatment but there was no statistically significant difference between the two groups.