The purpose of study is to determine the effect of using educational computer games on the motivation of students in regard to English language learning. The study was conducted using sixth grade students attending Vali Lütfullah Bilgin Primary School in Elazığ in Turkey. During the application period in which the quantitative research approach was used, an educational computer game related to the unit "Mathematical Problems" and designed by the researcher was presented to the students. The experimental group consisted of 33 students, while the control group consisted of 36 students. The experimental group was exposed to both the sixth grade English Lessons Program of The Ministry of Education (ELPME) and the educational computer game, while the control group was only exposed to the sixth grade ELPME. During the data collection period, a CIS (Course Interest Survey), developed by Keller and adapted to Turkish by Varank, was used to the determine students' motivation in regard to learning English. This tool was used as a pre-and end-test for both groups.As a result of the analysis, it was determined that the learning environments enriched by the educational computer games had a positive effect on the students' motivation, to a limited extend. Therefore, this study shows that educational computer games can be used to enrich learning environments at the primary education level. This study also revealed the necessity of extending the use of educational computer games in English learning.