The purpose of this research was to examine the effects of training in metacognitive, affective and social learning strategies of writing in improving students’ use of each of these learning strategies of writing. To this end, the selected Year-I students of Hawassa University were taught lessons of the Basic Writing Skills course with training in each of the three groups of the learning strategies of writing. Data were collected mainly through a pre and post-training five-point scale questionnaire. An interview was also held with selected participants. Paired-Samples T Test was computed to compare the pre and post-training mean scores of the students. The results showed that the training significantly improved the students’ use of the learning strategies of writing (t-values > -10.72, p-values =.000). Moreover, results of the interview revealed that the training made the students learn the importance of the strategies to improve their writing skills. Hence, they continued using the strategies appropriately in and outside the class to help them successfully accomplish their writing tasks. Based on the findings, recommendations have been made.