The invention relates to an electrophoretic display micro-unit, electronic ink, an electrophoretic display diaphragm and an electrophoretic display. The electrophoretic display micro-unit comprises a microcapsule, electrophoretic particles and an electrophoretic liquid, wherein the electrophoretic liquid is sealed in the microcapsule, the electrophoretic particles are located in the microcapsule and suspended in the electrophoretic liquid, and a stabilizer is added to the electrophoretic liquid and adopts polyisoprene. According to the embodiment of the invention, polyisoprene is taken as the stabilizer, the cost is lower, bistability of an electronic display can be effectively improved, and the switching time of the display is kept within a reasonable limit. Besides, polyisoprene contains double bonds, so that the operability is high, and bigger space is reserved for further improvement of the stability of the electrophoretic display.