Abstract The present study tried to investigate the impact of a proposed online multiple intelligences based program on developing the academic achievement of the English language students. Declining English language academic achievement among schools students have been reported over many years in Egypt. This study proposes using the multiple intelligences (MIs) theory in combination with the online learning approach as a remedial solution to overcome this problem. The researcher tried to integrate the benefits of MI approach with the advantages of online learning as an attempt to develop the students' English language academic achievement. The quasi- experimental design (control group and experimental group) was adopted for conducting this research. The participants of the study were 60 students randomly selected from the third year preparatory students. The study instruments were the online MI questionnaire and the pre-posttest English achievement test. Reliability and validity of the study instruments were proved.  The highest intelligences according to the results of the study online MIs questionnaire were the linguistic, visual-spatial, logical-mathematical and musical intelligences. That's why the researcher tried to make use of these intelligences in order to improve the students' academic achievement in English learning. The control group studied through the traditional instruction using the traditional methods of teaching, while the experimental group participants were taught through the proposed online multiple intelligences program with the designed MIs activities in light of Bloom's taxonomy of cognitive levels in order to evaluate the students' academic achievement. Results revealed that the experimental participants' academic achievement in English was significantly developed. They outperformed their counterparts in the control group. Therefore, it could be concluded that the implementation of the online multiple intelligences program was very effective in developing the English language for the preparatory school students.  In light of the study findings, a set of recommendations and future research suggestions were highlighted. Keywords: Online learning, Multiple Intelligences Theory, English language, academic achievement, preparatory school students.