Grammar is a fairly important aspect of writing because without someone knowing grammar well, the meaning they want to express to the reader would not be conveyed and it would be difficult to understand. In this case, it could not be denied that writing and grammar were related to each other. The purpose of this study was to find out whether there was significant correlation between grammar mastery and writing skill on the sixth semester students of English Education study program at UIN Raden Fatah Palembang. The method used in this study was a quantitative method and the technique used in this study was a correlational technique. The sample of this study was thirty four students taken from four classes of sixth semester students by using simple random sampling. In collecting the data, the grammar test and writing documentation were used. The findings indicated that there was a significant correlation between grammar mastery and writing skill which the r obtained .484 was greater than .338 in the r table with df = 32. The level of (p) significance (sig.2-tailed) was .004. It means that, (p) .004 was lower than 0.05. If the p-value was lower than 0.05 (p