This research is conducted on the basis of researcher’s observation that students got difficulties in learning English grammar. Students have good basic on Arabic grammar. The objective of this research is to find out the effectiveness of English-Arabic basic grammar bilingual module developed for students. Teacher also got constraint on time allocation. This research involved 66 students. Thirty two students were in the experimental class and thirty four students were in the control class. The researcher used R n D research according to Sugiyono. An instrument test to collect the data used test. They are pre-test and post-test and the type is multiple choices test. The result of this research described as follow. (1) The development of English-Arabic Grammar Bilingual Module was done by using seven steps of development suggested Sugiyono; identifying problems and potentials, designing the product, validating the product, revising the product, preliminary field testing of the product, main field testing of the product, and final revision of the product. (2) The effectiveness of the product was supported by the result of students post-test that obtained 77,97. (3) The extent needed of developing English-Arabic basic grammar Bilingual Module is as follow: (a) The need analysis was 60,99% means needed. (b) The validation result of external expert was 85,45% means valid. (c) Students’ perception obtained 76,07% means needed. The average percentage of those three items was 76,% that means needed. In addition, this English-Arabic basic grammar Bilingual Module is needed to be implemented in teaching basic grammar for the eleventh grade students of MA Salafiyah Kajen Pati.