This research is written base on the goal of determination the relationship between students study methods and achievement motivation with time management. For this matter, 341 high school girls were selected through the students of districts 2 and 4 of Tehran via cluster random sampling method. Also these 3 questionnaires: A) Study methods B) Herman's achievement motivation C) Time management, were distributed through them and finally the results were analyzed with several variables regression and Pierson Correlation methods. The results demonstrate that all of these three hypotheses are correct and it defined that there are a relationship between students study methods and achievement motivation, student's achievement motivation and time management, students study methods and time management. And it declared that the exploratory studies methods and careful reading have had the most affect on student's achievement motivation and time management as well. While, only 39.47% of students use these careful reading methods and it represent the students have not enough knowledge about the benefits of study methods and half of them are a bit familiar with time management skills.