Motivation is considered a complex and challenging issue in teaching, especially in second language courses. Many studies have been conducted about motivational strategies in teaching English language, however, the research that focuses on essay writing is still rare. Therefore, this research aims to describe the effect of the motivational strategies on students’ essay writing proficiency and their response to its implementation. These strategies include Creating the Basic Motivational Condition (CBMC), Generating Initial Motivation (GIM), Maintaining and Protecting Motivation (MPM), and Encouraging Positive Retrospective Self-Evaluation (EPRS). The research participants were third-semester undergraduates in a private university, in Indonesia, that enrolled in essay writing. The data were collected by conducting essay writing tests and interviews. The results revealed that there was a statistically significant impact on the students' writing scores, as observed from the improvement from their pre-test to post-test scores In addition, the data from the interview showed the students’ positive response and consciousness of their writing progress which indicated the appropriateness of the strategies in their class. The results showed the necessity of implementing motivational strategies as a new model of English instruction by writing lecturers and English teachers in general.