The aims of this research were: (1) to find out the kinds of students’ strategies
of achievement on vocabulary learning, (2) to find out the most dominant strategy
used by the students of achievement on vocabulary learning. The researcher applied
descriptive method in this research to grade IX students of SMP Negeri 1 Kalibagor
in academic year 2015/2016. Random sampling was used to get the sample which
consisted of 66 students from four classes. Data collected using questionnaire which
consisted of 25 items and each item consisted of five options. Data was then by using
percentage to determine which strategies were used by the students in learning
vocabulary and what vocabulary learning strategy dominantly used by the students.
The results were: each student employed all of vocabulary learning strategies. There
were 30 students who used determination strategy and the percentage which reached
69.15%, 19 students used memory strategy and the percentage which reached
66.36%. On the other hand, social strategy was used by 7 students and the percentage
which reached 60.12%. Metacognitive strategy was used by 5 students and the
percentage which reached 58.12%, and cognitive strategy used by 5 students and the
percentage which reached 57.52%. So, the dominant strategy used by the students
was determination strategy.