This research was conducted to investigate 6th grade students' problem solving strategies and whether these strategies change with problem type and number structure of problems. 165 randomly selected students of grade six participated in this study. A problem test which contains proportional and non-proportional word problems was designed as a data collecting tool. Number structures also considered in the problem test. Descriptive data analysis methods were used in this study. Analysis has shown that students used 7 different strategies on solving proportional problems and 6 different strategies on solving non-proportional problems. (C) 2015 The Authors. Published by Elsevier Ltd.