Large mode area (LMA) photonic crystal fibers have characteristis of endlessly single mode and large mode area. These characteristics overcome the limit of high power systems caused by nonlinearity due to the high power density, especially the ultrafast pulse systems. The excellent characteristis of the LMA photonic crystal fibers make them have a subject of enormous interest in areas such as high-power fiber laser, fiber amplifier, high-power energy transmission, and high sensitivity sensor. The research of LMA photonic crystal fiber is reviewed in terms of the characteristic parameters, design methods, applications, and so on. Their development prospects are also discussed.