The paper investigated the most and the least factors of student-generated vocabulary testing that can influence EFL learners’ autonomy. This study applies mixed-method research. For the qualitative phase, the researcher used 30 purposive participants and had a semi-structured interview to find the factors and make a questionnaire. The researcher used MAXQDA to analyze the data. Then the researcher prepared a questionnaire and distributed it among 225 convinced participants, making it reliable and valid. The reliability of this questionnaire was 0.92. For the quantitative phase, the researcher used 320 EFL learners who participated. The study instrument was a research-made questionnaire about the factors of student-generated vocabulary testing that can influence EFL learners’ autonomy consisting of two sections. The mean values of the four variables obtained from the participants’ viewpoints reveal which factors of the student-generated vocabulary testing have the most and least effect on autonomy among Iranian EFL learners. After analyzing the questionnaire, the researcher used 30 participants (13 males, 17 females) by random sampling for the qualitative phase to ask them about their point of view of SGVT and its effect on their autonomy. For analyzing the data, the researcher again used MAXQDA. The results of this study show that the most influential factor was ‘Personal characteristics. ‘Teachers’ role’ was determined to be the second significant factor. ‘Positive points of student-generated testing were in the third place, and the least effective one was ‘Negative points of student-generated testing. Manuscript profile

The present study aimed at investigating student-generated vocabulary testing factors fostering autonomy among Iranian EFL learners. The changing needs of today's society have redefined the goals of education in general and teacher and learner roles in particular. Learners are no longer viewed as the individuals who passively receive knowledge from teachers. Instead, the modern society has necessitated a lifelong learning, that is, training learners by giving them the power to take the responsibility of their own learning. The qualitative method of research was used in this study. The participants consisted of 30 EFL learners studying or finished teaching English. A semi-structured interviews were designed and conducted. After conducting all the interviews, the recorded interviews were transcribed by the researcher. In order to maintain the confidentiality, each participant was given a name other than his or her real names. Then, the transcripts and interviews' notes and memos returned to the participants and they were asked to ensure that the data was genuine and truly based on their opinions. Then, the transcripts were read and reread several times in order to thoroughly comprehend and get familiar with. In this qualitative research, MAXQDA software was used to analyze the data. A large number of codes were consequently provided by the software and a list of tentative categories were prepared (4 themes and 14 categories) by the constant comparative method. The four themes are: 1- Personality characteristics 2- Positive points of student-generated vocabulary testing, 3- Negative points of student-generated vocabulary testing, 4- Teacher’s role. Manuscript profile