In this study, the authors have tried to analyze and evaluate writing proficiency as a criterion for language proficiency in the end of secondary school among graduates who prepare themselves for entrance examination of universities. The objective of the present research is to evaluate the level of secondary school graduates’ writing proficiency .To do this, a questionnaire and a standard test were used as research methodology’s tool. Four hundred students from Tehran school were selected to participate in this test whose validity and reliability have been already confirmed. The main features in evaluating graduates proficiencies have been regulated based on educational purposes and the guide of curriculum. The proficiencies like spelling, applied grammar, summarizing, and writing were examined. The benchmark score is based on the usual routine of education, 12 (out of 20), and the lowest level of graduation, the lowest grade of 12 was equivalent to 60% of the total score. According to the educational goals of writing proficiency, official programs and reference documents, the results showed that most of graduates have not acquired the necessary writing proficiency and have not reached the level of mastery and graduation. The spelling had the best status in the way that at least fifty percent (50%) of graduates could gain satisfactory score. Finally, the summarizing had the most unfavorable situation where only 13% of the graduates obtained average score.