This course is the elected course for graduate students in Optoelectronics Science and Technology. After the completion of this course, students should know the following items. (1) The basic priciple of ultrashot lasers, (2) Property of ultrashort pulse, (3) The modulation of ultrashort pulse, and (4) the application of ultrafast lasers. Students will need to grasp the basic principle of ultrafast short pulse, learn and cultivate the ability to analyze and solve the problem in the filed of ultrafast photonics, and in-depth understanding of their physical concepts. It is essential for students to engage in research and development of optical information technology in the future.