The purpose of this study was to compare the developmental differences between conce
pt and meaning of the two groups which are ordinary and children with mental retarded
with mind map analysis. Sixty ordinary children and sixty mental retarded children who
were five, six, and seven years old were participated. Fourteen target words were suggest
ed to approach mind map strategy. The results were that:(a) the two groups developed
the total numbers of vocabularies with increasing age, even though the mental retarded ch
ildren delayed to develop the total number of vocabularies; (b) ordinary children develope
d the concept words based on their age, however the mental retarded children did not; (c)
the two groups developed the meaning words based on their age, although the mental reta
rded were delayed; and (d) there was the effective correlation between concept and meani
ng words. Therefore, this study concluded that concept words is considered prior to meani
ng words to teach vocabularies for mental retarded.