This study was aimed at : (1) developing an instructional multimedia design for teaching line and angle to the seventh grade students of junior high school; (2) describing the result of the implementation of the multimedia using GeoGebra as media of exploration, Camtasia Studio as an application for sound and video editing, Lectora Inspire as the application for making layout and quiz;(3) finding out the validity of the multimedia for teaching line and angle to the seventh grade students of junior high school. The study used DDD-E model that consists of deciding, design, develop, and evaluate stages. The product was tried out in several stages which were done by instructional materials experts, and students at different schools and used qualitative and descriptive quantitative data analysis techniques. The result showed that the multimedia for teaching line and angle could be accepted as instructional media with the average score of 43.5 from the instructional material experts falling into valid criterion, and the mean score given by the material experts was17 falling into valid criterion. The multimedia that has been developed also got a very good response from the students with the average score of 47.63. Based on the result that has been obtained, the multimedia that has been developed as a good qualification and is good for use in the process of teaching the topics of line and angle
