This study is conducted to examine the effect of input enhancement as an implicit and consciousness-raising as an explicit method of instruction on improving grammatical and lexical collocation knowledge of Iranian EFL learners. To reach this aim, a sample of sixty participants at pre-intermediate level of English proficiency in Gorgan, Golestan, Iran was selected. They were randomly assigned to one control and two experimental groups. All of them were given a pre-test to assure that they were homogeneous with regard to their knowledge of collocations. All groups received the same text with different methods of teaching during the six treatment sessions. One week after the last treatment session, a posttest was administered to them. The results of the study revealed that input enhancement had no significant effect on increasing the grammatical collocation knowledge of Iranian EFL learners, while it had a significant effect on the improvement of lexical collocation knowledge. In addition, consciousness-raising instruction had a significant effect on increasing both lexical and grammatical collocation knowledge of Iranian EFL learners. Besides, consciousness raising group outperformed the input enhancement and control group. This study offers some pedagogical implications for syllabus designers, material developers, teachers, and students.