Problem statement: This study aims to investigate factors influencing mathematic problem-solving ability of sixth grade students. One thousand and twenty eight of sixth grade students, studying in the second semester of academic year 2007 were sampled by stratified random sampling technique. Approach: The research instruments used in the study included mathematic problem-solving ability test and questionnaires. Data was analyzed by Path Analysis. Results: Factors influencing mathematic problem-solving ability were represented as following: (1) direct factors influencing mathematic problem-solving ability were described that direct and indirect factors influencing mathematic problem-solving ability were attitude towards mathematics, self-esteem and teachers' teaching behavior. Indirect factors influencing mathematic problem-solving ability were motivation and self-efficacy (2) factor models influencing mathematic problem-solving ability of sixth grade students was associated with visual data (3) The developed model could describe variance of skill in mathematic problem-solving at 63.00 % (R[superscript 2] = 0.63). Conclusion: Teachers' behaviors took both direct and indirect effects on the students' mathematic problem solving. The teachers are supposed to study the methods to develop this ability deeply and then bring them to manage the activities in class that encourage students to be enthusiastic to learn and have good attitude toward mathematic learning or to get students' concentration. (Contains 1 figure.) [Financial support for this research was provided by Mahasarakham University.]