The aims of this research were to find out: (1) the students’ vocabulary
knowledge breadth level; (2) the students’ reading comprehension level and (3) the influence
of students’ vocabulary knowledge breadth on reading comprehension of the second grade
students at SMA NegeriBaturraden in academic year 2013/2014. This research was corelational
in nature and the participants were 48 students or 21 percent of the population
(228). The technique which was used to determine the participant was purposive sampling
technique. The data was collected through two kinds of test namely Vocabulary Level Test
(revised version) which was developed by Paul Nation and reading comprehension test. The
correlation computation was computed by Pearson Product Moment. The result of the
analysis showed three results. The first was the result of the students’ vocabulary knowledge
breadth computation. The average was 1392 words or it was 70 % text coverage. It could be
said the students’ vocabulary knowledge breadth was in good level category. The second
students’ reading comprehension test average was 71.96 %. It meant the students’ reading
comprehension was in good level category. The third was the result of coefficient correlation
between students’ vocabulary knowledge breadth and students’ reading comprehension was
0.934, this was higher than critical value taken from r table (r-table=0.291) where the degree
freedom (df) was 46 at the significant level of 0.05. The correlation was categorized as high
correlation. It meant that null hypothesis (H0) was rejected and alternative hypothesis (H1)
was accepted. It indicated that there was positive high significant influence of students’
vocabulary knowledge breadth on reading comprehension.