In this study, it was aimed to be analyzed mathematical and linguistic complexity of the problems posed by sixth grade students over the open-ended verbal story about fractions. The study was conducted with 170 students receiving education at the sixth grades of seven middle schools located in the city center of Erzurum. Descriptive research method which is appropriate to quantitative research approach was utilized in this study. The students were given an open-ended verbal story and they were asked to pose two verbal problems. The problems posed by students were analyzed in terms of their mathematical and linguistic complexity. The problems were categorized into groups of “assignment”, “relational” and “conditional” according to their linguistic complexity. It was determined that students had difficulties in the problem posing for the operation with fractions. Additionally, it was determined that the students preferred the “assignment” type of problems more than the other types in problem posing process.