In this study, it was aimed to identify the relationship between composition writing success of 6th grade primary school students and the variables of their writing disposition, gender, parents’ education level, summarizing, and noting. 120 students from three primary schools in Mersin compose the sample of the study. In the study, Writing Disposition Scale which was developed by Piazza and Siebert (2008) and adopted in Turkish language by İşeri and Ünal (2010) was used. Moreover, rubric to assess composition writing success which was developed by Ömür (2009) was used. Spearman Rank Correlation was applied between the points of sub-scales of continuity, confidence and passion within the writing disposition of students and their composition success and positive but slight relationship was found. In order to identify the gender, summarizing and noting conditions of composition writing success of participants Mann-Whitney U test was applied and the difference was found statistically significant. In an attempt to identify the difference between composition writing success and parents’ education level Kruskal-Wallis test was applied and no statistically significant difference was found. Furthermore, it is found that composition writing success of participant which is related with gender and noting conditions is also related with their writing disposition. The results of study were identified with 95% reliability interval.