This study aimed to determine the effect of vocabulary instruction integrated with writing exercises on vocabulary learning, retention, and awareness. The research was designed according to the sequential explanatory mixed-method design, in which quantitative and qualitative methods were used together. A quasi-experimental model with a pretest-posttest control group was used in the quantitative phase. The study group of the quantitative stage consisted of 76 seventh-grade students in two experimental and one control group. The target words were taught according to the vocabulary instruction integrated with writing exercise in group A, enriched vocabulary instruction in group B, and traditional vocabulary instruction in the control group. In the qualitative phase, the participants were interviewed to determine to what extent they had learned the target words in terms of meaning and use. For this, three students from each group were selected and these students were interviewed about specific target words during the intervention. In addition, at the end of the intervention, the opinions of the students and their teacher in group A were elicited. Quantitative and qualitative findings revealed that vocabulary instruction integrated with writing exercises contributed to students' better learning of target words, the permanence of their learning, and the development of word awareness.