Writing is one of important language process and teaching language because these elements include one of four elements basic language skill. Nevertheless, in SMAN 1 Kandat, the writer found the most of students there still get difficulties in studying as specially writing subject. With has many vocabularies and grammar achievement will be influence the writing ability. Hopefully, the students get a big opportunity to express with their own word to writing story and try that give teacher. The objective of this research is (1) To describe how to vocabulary achievement at SMAN | Kandat. (2) To describe how to grammar achievement at SMAN I Kandat. (3) To describe how to writing ability in descriptive text at SMAN | Kandat. (4) 4.To find whether there is simultaneous significant correlation among the skill of vocabulary achievement and grammar achievement toward writing ability in descriptive text among the tenth grade students of SMAN 1 Kandat. (5) To find whether there is partial significant correlation among the skill of vocabulary achievement and grammar achievement toward writing ability in descriptive text among the tenth grade students of SMAN 1 Kandat. The design of the study is descriptive quantitative approach as the research design. The method is correlation, and the techniques of collecting data were test. The quantitative was related to the computation of number. The correlation was related to find the relationship all variable. The research instruments in this research is test. There were tests used in this research related to vocabulary and grammar and writing in descriptive text, the first test which related to vocabulary achievement and grammar achievement contained 50 numbers. The last test which related to the wniting ability in descriptive text is | numbers essay. To correlate three variables, regression and partial was used. Students in second semester were taken as population consisting of 151 students and 110 as samples. The result of vocabulary achievement belongs to very good category. It is
proven that the 39 students have very good average vocabulary achievement.The mean is 73.75 and the percentage of this category is 40%. For their grammar achievement belong to low categories. It is proven that the 32 students have low average grammar achievement.The mean is 46.58 and the percentage 29.09% in this category. For their writing ability in descriptive text belong to high category. It is proven that the 41 students have high average writing ability.The mean is 61.45 and the percentage is 41.81%. Then, to correlate among three variables it used regression technique. The result of Vocabulary achievement belongs to the high category. The result of the correlation among vocabulary achievement and grammar achievement toward writing ability in descriptive text at the tenth grade students SMAN 1 Kandat shows the multiple correlations among vocabulary achievement and grammar achievement toward writing ability in descriptive text. The table contains number of regression, number degree of freedom, and
significance level. The correlation used here multiple linier Regressions which . value is 0.958. The significance level is 0,00(a). It means that the degree of error to accept hypothesis is 0.00. It is higher than 1% significance level. So, the result is significant at 1%. It means that hypothesis alternative is accepted. Then for the significant partial correlation among vocabulary achievement and grammar achievement toward writing ability in descriptive text at tenth grade students of SMAN 1 Kandat can explained after this. Firstly, the result of the partial correlation among vocabulary achievement and writing ability in descriptive text controlied by grammar achievement at tenth grade students of SMAN 1 Kandat showed that the value of significant leved at to tailed or at the level of significance 1% by SPSS was 87,7% and the number of significance showed that (to tailed) 0.000.It means that there is significant partial correlation among vocabulary achievement and writing ability in descriptive text controlled by grammar achievement at tenth grade students of SMAN | Kandat .secondly, the result of the partial correlation among grammar achicvement and writing ability in descriptive text controlled by vocabulary achievement at tenth grade
students of SMAN 1 Kandat showed that the value of significant leved at to tailed or at the level of significance 1% by SPSS was 8,5% and the number of significance showed that (to tailed) 0.000.It means that there is significant partial correlation among grammar achievement and writing ability in descriptive text controlled by vocabulary achievement at tenth grade students of SMAN | Kandat .On the other hand the vocabulary achievement and grammar achievement are highly correlated to writing ability in descriptive text. Based on the statement of problems there are the correlation among vocabulary achievement (X1) and grammar achievement (X2) toward writing in descriptive text (Y).So, the first hypothesis is accepted. It means that the accuracy of H1 rejection is 100% right and 0% wrong. The value of Ho rejection is 1% and the value of H0 accepted is 99%.it’s mean writing in descriptive text is influenced by vocabulary and grammar. The result is recommended by Fitriyah (2012)” The Correlation between Vocabulary Achievement and listening Ability among The Second vear students of SMAN I Pare in 2012”. Based on the results of correlation above, (1) for the teacher it is recommended to support their students’ vocabulary belief though the students’ grammar score to high and that can increase students’ writing skill. (2) For the students, it is recommended that they should believe about their ability, and always be confident to learn English, and the last, (3) for next researchers who want to conduct the research in the same field, it is recommended to use other variable such as motivation, age, etc. to enrich and strengthen the findings.

Key Word: Correlation, Vocabulary, Grammar and Writing in descriptive text.