This research aimed to find out the effectiveness of using educational games in teaching vocabulary and grammar for 6th year primary school pupils. For this purpose, two intact groups were selected and assigned to an experimental group and a control one, twelve pupils in each group, from Complex Quran Memorization School (Primary School) in Gezan, Kingdom of Saudi Arabia during the first term 2018-2019. The researcher used a quasi- experimental design. The researcher used the communicative approach and educational games to teach vocabulary and grammar for the experimental group, whereas the control group received regular instruction by using the communicative approach only. The researcher prepared vocabulary and grammar test. Pupils in both groups were pre-tested using the vocabulary and grammar test. After that, the researcher used the educational games for teaching the experimental group, while the control group received regular instruction. Finally, the same vocabulary and grammar test was post-tested on both groups. The data obtained were statistically analyzed. Findings indicated that the experimental group exceeded the control group in vocabulary and grammar posttest. Thus, the educational games proved to have a large effectiveness in teaching 6th year primary school pupils'' vocabulary and grammar.