To meet the need for measurement of state of polarization (SOP) altering in high speed, a new technology to realize high-speed state of polarization measurement was proposed. A general means of state of polarization measurement using polarizer and quarter wave plate (QWP) was given, and based on this technology new formulas which can both meet the requirement of high-speed and real-time state of polarization measurement are brought out. To validate the feasibility and stability of the new theory, a particular project of experiment is made. The experimental system can perform over 700 polarization measurements per second, the results show that, measuring speed is mainly determined by the performance of the electronic parts and thus the measuring speed can be greatly accelerated by improving electronic parts of the system, the result is also proved to be credible and stable, and the method is useful.