本研究旨在發展一份適用於國小三年級學生之單位詞測驗，初步分析普通學生和閱讀障礙學生之單位詞能力發展概況，以比較兩者之間的差異，並進而探討單位詞、識字、詞彙與閱讀理解能力的相關。為達上述目的，本研究以南縣某一國小年級學生為研究對象，其結果如下： 1.國小三年級學生之單位詞測驗具有良好的信效度。 2.普通學生和閱讀障礙學生在單位詞測驗上之得階，有顯著的差異；而兩組學生分別在「分類詞」、「量詞」與「動詞單位詞」三類別之得分並無顯著差異，可將三類別為同一種單位詞能力。 3.普通學生在單位詞、識字、多向度詞彙與閱讀理解測驗上之表現的相關是很相近的；而閱讀障礙學生在單位詞測驗與識字測驗上之表現的相關並不同於單位詞測驗與多向度詞彙測驗和閱讀理解測驗上之表現的相關。 4.兩組學生在單位詞測驗上填寫的錯誤答案有許多相似之處，但錯誤出現次數則有差異，其錯誤組型可分為語義混淆、用法混淆、事物分類概念混淆與不明錯誤四種。 5.依照閱讀障礙學生在各項測驗上的表現分為識字較優組、單位詞能力較優組、閱讀理理能力較優組、多向度詞彙能力較優組及各項能力皆差組五種亞型。 本研究並針對研究結果，提出對未來研究、教學與評量的建議。

　　　　　The purposes of this study were first to develop the classifiers test battery for 3rd graders, and secondly to compare the classifiers competence the relate to word recognition, vocabulary, and reading comprehension the 3rd graders with and without reading disability. The main findings of this research were stated as follows: 1.These classifiers tests possess acceptable reliability and validity. 2.There were significant differences between the 3rd graders with and without reading disability in the scores of classifiers test. Also, to find normal students have significantly intra-individual differences. 3.The scores of classifiers test and word recognition, vocabulary, and reading comprehension of the 3rd graders without reading disability were relevant. However, the relationship scores of classifiers test and word recognition were not similar to the relationship scores of classifiers test and vocabulary, and reading comprehension of the 3rd graders with reading disability. 4.There were similarities between the 3rd graders with and without reading disability in error patterns. But two groups have significant differences in error frequencies. The distinguishing error patterns for using classifiers could be divided into four types. 5.The 3rd graders with reading disability could be further divided into five subtypes based on their test scores of classifiers, word recognition, vocabulary, and reading comprehension.