Any policy that aims to solve the challenges of language teaching and learning must include language assessment research. Language assessment has shown a lot of development in terms of the scientific implications of assessing language capacity for the purposes of advising judgments about people and reviewing language programs (Bachman, 2000). The aim of this research was to look into the relationship between using Dynamic Assessment methods and the writing skill of Iranian EFL students, as well as the impact of DA on student motivation. Secondary school male students from Teheran's "Mofid" private high school were chosen to participate in this study to accomplish this goal. A general proficiency test (PET) was provided to all participants, which classified them into five levels. The listed exam leveled pre-intermediate students, who were then split into two classes. They were almost equal in terms of scores, materials, and ages. After reviewing and scrutinizing students' pretests for the required pre-existing information and techniques, resources were provided to the experimental community in the form of mediation pages, instructor explanations, and constructive input. Correspondingly, to determine the impact of the Dynamic Assessment procedure used in this study on students' motivation and attitude, a Persian-language version of the Attitude/Motivation Test Battery (AMTB) was provided to secondary school students studying English as a foreign language, which included each scale mentioned in the' AMTB item key document (R. C. Gardner, 2004). After ten sessions of treatment, patients were given a post-test that was similar to the pre-test but with new content to see whether DA had any impact on them. The findings revealed that there was no statistically important difference between the Pre and Post-test results. As a result, it was determined that the null hypothesis had not been denied. The findings of the motivation test, on the other hand, revealed that the correlation between pre and post-test was important and that DA had a positive impact on participant motivation.