The objective of the study is to know the effectiveness of teaching vocabulary by using pictures to the fourth grade students of SDN Pondok Pinang 01 Pagi in the 2009/2010 academic year. The method of this research is experimental research with true experiment technique which is the writer took two different classes to be observed there are IVA class as an experiment class and IVB class as a control class. The writer also taught and gave pre-test and post-test for both of classes. The pre-test was held on 18th of March 2010, and the post-test was held on 15th of April 2010. The tests were held for both of classes to know the effectiveness of teaching vocabulary by using pictures to the fourth grade students of SDN Pondok Pinang 01 Pagi. For this research, the writer took 101 students as the population from IVA and IVB class of SDN Pondok Pinang 01 Pagi in the 2009/ 2010 academic year. The number of student from IVA class was 49 students. The number of the student from IVB class was 52 students. But the writer only took 29 students from each class to make sampling. Thus, the total samples from two classes were 58 students. The writer implemented t-test formula for analyzing the data. The writer gets tobserved (th) = 2,45 and ttable (tt) = 1,67 with significant (α = 0,95) and freedom of degree (dk) = (n1 + n2) ? 2 = 56. It means th > tt. Thus, the alternative hypothesis (Hi) is accepted and the null hypothesis (H0) is rejected. It concluded that teaching vocabulary by using pictures is effective to the fourth grade students of SDN Pondok Pinang 01 Pagi in the 2009/2010 academic year