eng Science and Education Publishing American Journal of Educational Research 2327-6150 2018-12-26 6 12 1688 1692 10.12691/education-6-12-15 EDUCATION201861215 article Delima Simanjuntak delimasimanjuntak23@yahoo.co.id 1 E. Elvis Napitupulu 1 Martua Manullang 1 Rismalyah Manalu 1 Lamtiur Sinambela 2 State University of Medan, Medan, Indonesia Pelita Harapan University of Medan, Medan, Indonesia The aim of this study is to analyze whether there is enhancement difference of student mathematical problem solving ability (MPSA) taught by guided discovery learning model (GDLM) and direct learning model (DLM). This study is quasi experiment study. The population of this study is seventh grade student of junior high School (SMP N 2 Kutalimbaru). The sample of this study is two classes of seventh grade of junior high School (SMP N 2 Kutalimbaru) which is taken randomly. The experiment class is taught by GDLM and the control class is taught by DLM. The result of this study shows that there is enhancement difference of student MPSA taught by GDLM and taught by DLM. N-gain of student taught by GDLM is higher than student taught by DLM. http://pubs.sciepub.com/education/6/12/15/education-6-12-15.pdf problem solving ability guided discovery learning model direct learning model