In this study, we proposed a web-based annotation and search system named WASS, which not only provides annotation making but also peers’ annotation searching and reviewing for vocabulary learning. Four-week experiment was conducted among 75 vocational high school students, divided into experimental group and control group. The student learning behavior and their influence on learning achievement were explored, the results showed that experimental group outperformed control group in vocabulary post-test. Further investigation in experimental group showed low achievement students made more text annotation than the high achievement students and obtained more significant score gain, thereby indicating that our system is capable to motivate the low achievement students to make more text annotation, this is because through searching and learning peers’ annotation, low achievement students can make more annotation and acquire more vocabulary. Those findings may confirm that searching and reviewing peers’ annotation plays an important role in fostering vocabulary learning, especially for those low achievement students in vocational high school. Therefore, designing the supported powerful function to utilize annotations completely is vital (like searching tool for peers’ annotation in this study) and encouraging students to learn through their own annotation and peers’ by searching tool.