The objective of this study is to describe the implementation of crossword puzzle and to identify the factors influence the implementation of crossword puzzle to enrich the students’ vocabulary. The research was conducted on four grade students in MI Miftahul Ulum Pancur 1 Mayong, the total of the students is 28. The researcher used descriptive research during the research. In collecting the data, the researcher uses classroom observation and interview. The researcher conducted classroom observation about two meeting; in every meeting the teacher gave task to the students. In every meeting the students got new vocabularies from crossword puzzle. The researcher analyzes the mean score of each task to find out the improvements of students’ vocabulary mastery using crossword puzzle. Interview done after classroom observation, the researcher interview the teacher and some of students. In the classroom observation could be seen that that there were many more new words that could be learned about crossword puzzle. The students could enrich their vocabulary in two test that had been by the teacher. The students could identify the word into form of verb, adjective, and noun, the students known the meaning of new vocabulary and the students could be complete the task. Furthermore, the data which was collected by using interview also showed that using crossword puzzle had strength and weakness. The strength of the technique was technique could support in teaching and learning process. The students could easier to learn and more active in the classroom. The weakness of the technique was technique made the students paid attention to the teacher, because some of the students never heard the vocabulary. By using crossword puzzle in teaching vocabulary, students could easily understand and memorize new vocabulary. It is suggested that technique in teaching English can be recommended for the English teachers. In the teaching learning process, when the teacher uses crossword puzzle technique, the students are enthusiastic and enjoy during teaching learning process.