ABSTRACT Andrianto. 2014. ?The Implementation of 2013 Curriculum and Students? Learning Achievement at The First-Grade of SMA Negeri 5 Purworejo in the academic year of 2013/2014?. A Thesis.English Education Department, Faculty of Teacher Training and Educational Science, Muhammadiyah University of Purworejo. Consultant: Semi Sukarni, M.Pd. Keywords: Implementation, 2013 Curriculum, Students? Learning. English is one of languages that are used by people in the world. Almost allcountries have adapted English used as a compulsory subject at schools.Considering the important of English as International language, Indonesian government enters English learning in their curriculum that will be learned by Indonesian learners. But, the older curriculums had several problems such as; too many subjects being learnt,curriculum was not fully based on competency, etc. So, the Indonesian government has decided to rethink, reformulate, and redesign the curriculum into the 2013 curriculum. It is aimed at improving the quality of processes and outcomes of education, which leads to the formation of good character and noble character of students as a whole, integrated, and balanced matched with the competency standards in any educational institution. However, most of teaching institutions don?t prepare yet for the teachers to the 2013 curriculum. The problems on this research are (1)how the teachers implement the 2013 curriculum in teaching English to students; (2)how the students learning achievement using 2013 curriculum. The respondents are students of the first-grade of SMA Negeri 5 Purworejo in the academic year 2013/2014. The total of respondents are 34 students by applying simple random sampling. In getting the data, the researcher usesobservation and documentation. The researcher analyzes the data by using descriptivequalitative research. The researcher analyzes each item in observational sheet to the teacher and measured the mean, modus, median of students? score from the teacher to know the students? achievement. The main results of this research are (1) the teachers are implement most aspect in the observation sheet in implementing the 2013 curriculum in teaching English to students. It is based on the observational to the teachers did 85.06% from the total items included of pre-activity, core activity and closing activity and missed 14.04% ; (2) the students? learning achievement of the first grade students of SMA N 5 Purworejo in the academic year of 2013/2014which used 2013 curriculum is good. It is based on the mean of the students? result is 71.76, the category is good.