Background and objective: Students entering Zanjan Medical Sciences University lack the necessary proficiency in English to advance their knowledge in medicine. At university they have to pass many compulsory English courses as partial fulfillment of their degree. However, the final outcome is poor and bleak. The problem may be due to poor teaching methods and texts. Grammar-Ttranslation Method of teaching English has been a rule here rather than an exception. Therefore, the former has been compared with the modern Communicative Language Teaching Method to observe the outcome.

  Material and Methods: Two groups of the environmental health students were non-randomly chosen, and were randomly assigned to two classes. Each of the classes was taught with one of the methods under consideration. The course lasted about one academic term. Before the beginning of the course, a preliminary TOEFL test was administered to tap both groups level of proficiency. The same test was repeated at the end of the term. Later, results of both tests were analyzed and compared using tables and t-tests.

  Results: Analysis of data confirmed our hypothesis that there is a relationship between language teaching method and learning the language (p=0.431). The findings of the research also confirmed the fact that test distribution was normal and balanced.

  Conclusion: In general the findings of the study confirmed the proposed hypothesis. The mean difference between the scores before and after the intervention was meaningful (p=0.046). The difference between means of scores in the old method was 1.07 whereas the difference between means of scores in the new method was 1.575, which was significant. Hence, using the new method is highly recommended.