This study compared the impact of two types of teacher written feedback on Iranian EFL learners' writing ability and their ability of tense consistency in L2 writing.After administering a standardized language proficiency test(Preliminary English Test),62 homogenous participants were assigned to the control(direct-only correction)and experimental(direct metalinguistic correction) group.The comparison of the groups on the writing pretest confirmed the homogeneity of the subjects before the instruction.During 10 sessions of instruction,the control group received direct-only correction by indicating the location of an error and the provision of the correct form,while the experimental group received direct metalinguistic correction by indicating the location of an error, writing the correct form,and providing metalinguistic comments explaining the reason behind correction.After the treatment,both groups took part in the writing and delayed writing posttests,respectively.The results indicated that direct metalinguistic correction was more effective in the improvement of EFL learners' writing ability and their ability of tense consistency and this improvement was retained over 3 weeks.