With the development of digital technology, image records were commonly used in children's behavioral observations. With simple video recording equipment, we can provide rich and diverse content. Therefore, the image recording strategy had become a popular trend. But many researchers still accustomed to translate the recorded images into textual information, the required resources and time to spend would be considerable. This study proposes a Child-Behavior Observation System (CBOS) to help parents to observe and record child behavior. Parents use DV to capture children's activities in the corner and send the real-time images to CBOS. Through the CBOS, parents can choice the picture exactly that they want to observe and draw some symbols on the captured images. Then parents can add textual descriptions for these symbols. Finally, parents can easily convert these records into a web page file or a Word file so that they can discuss the observed behavior with their children to increase the interaction between parents and children.