There is a general consensus that writing is a challenging task for students with learning disabilities (LD). To identify more precisely the extent and depth of the challenges that these students experience with writing, the authors conducted a meta-analysis comparing the writing performance of students with LD to their typically achieving peers. From 53 studies that yielded 138 effect sizes, the authors calculated average weighted effect sizes, showing that students with LD obtained lower scores than their peers on the following writing outcomes: writing quality (-1.06); organization (-1.04); vocabulary (-0.89); sentence fluency (-0.81); conventions of spelling, grammar, and handwriting (-1.14); genre elements (-0.82); output (-0.87); and motivation (-0.42). Implications for research and practice are provided based on these findings.