The purpose of this study was to compare the types of morphological and syntactic errors in written simple and complex sentences produced by children with developmental language disorder (DLD) and children with typical language (TL). We analyzed the writing products of 30 children with DLD and 33 children with TL for morphological (e.g., past tense "-ed" and BE verbs) and syntactic (e.g., word omission and word order) errors in simple and complex sentences. We found that children with DLD produced more regular and irregular past tense errors and syntactic errors than children with TL. We also found that the number of total errors produced by children with DLD was not different in simple versus complex sentences. The findings reported can be used as a starting point for adding writing assessment to speech-language pathologists' tool kit for serving children with DLD. We recommend that clinicians begin with analysis of past tense and syntactic errors when evaluating narrative writing skills of children with DLD.