This research was carried out to reveal the impacts of word creation knowledge teaching on vocabulary of the students learning Turkish as a foreign language, and the research was performed with the use of quasi-experimental design with pre-test and post-test control group, which is one of the quantitative research methods. The study group of the research consists of 26 foreign students learning Turkish at B2 level at Ondokuz Mayıs University in 2016-2017 academic year. The application process of the research was carried out within the last 8 weeks until the completion of the educational program for the students at B2 level, which started on April 3, 2017 in Turkish Teaching Practice and Research Center at Ondokuz Mayıs University. The collected data and analyses have shown that the students learning Turkish as a foreign language benefited significantly from the derivational morpheme teaching, that the reading competence of the experimental group improved more effectively than the control group. It has also been determined that learners' success in terms of reading competence was influenced by the origin and structure of their native languages. It is believed that using the strategy of guessing meaning of unknown words based on word creation knowledge by learners has an impact on this achievement.
Word creation knowledge, derivational suffix, morpheme teaching, reading competence, Turkish teachin