The Correlation Between Students’ Mastery on Lexical Collocation and Their Writing Skills at English Education Department IAIN Zawiyah Cot Kala Langsa

English is one of the international languages that is used by many people in the world. It is the foreign language used by the Indonesian. It is learned in schools. In the education, it is one of the subjects applied from basic education to university. English develop the four skills namely listening, reading, speaking, and writing. In writing, there are some common problems found by students such as; grammatical, mechanical, and collocation. The students made many mistakes in writing collocation. It is caused by students have lack of knowledge about collocation. Students often use incorrect collocation in their writing, which is inappropriate with the pattern. Incorrect collocation in writing is one of the constraints for the learners to achieve good writing quality. This thesis focuses under the title The Correlation between Students’ Mastery on Lexical Collocation and Their Writing Skills. The problem in this study is students difficult to combine words in writing. The goal of this study is to find out whether there is correlation between students’ lexical collocation mastery and their writing ability at English department student of IAIN Zawiyah Cot Kala Langsa. The population of this study is the students of fifth semester. The samples of this study are one of class of fifth semester. This is a quantitative research. This research uses the correlation method. The writer made the test as instrument in collecting data and used product moment and t-test formula to calculation. The result is that the value of correlation thitung = 6,572 higher than ttabel = 1,734. It means that there is high correlation between students’ understanding of collocation and their writing ability. The conclusion that there is significance correlation between them and the hypothesis is accepted.