This correlational research was aimed to find out whether there is a positive correlationbetween field dependent cognitive style and mathematical conceptual understanding ofstudents who was taught by direct instructin and STAD model. The population of thisresearch was all students of grade eighth of a Public Junior High School in LampungSelatan. By cluster random sampling technique, there were two classes of research sample.The test method was applied to collect the data. The instruments of this research were GEFTand test of mathematical conceptual understanding of line equation material. Based on theresult of hypotesis test, it was concluded that (1) there is a positive correlation betweencognitive style and mathematical conceptual understanding on students who was taught bydirect learning model and (2) there is no positive correlation between cognitive style andmathematical conceptual understanding on students who was taught by STAD learningmodel. This result implies that learning model affects mathematical conceptualunderstanding of student who has field dependent cognitive style.