The invention provides a squirrel-cage type self-rinsing micro-bubble generator applied to air floatation treatment of oily sewage and industrial wastewater. A stock solution forms rotating flow on a rotating blade, and then enters a micro-porous membrane pipe to improve the utilization rate of gas; a ceramic-membrane membrane pipe ensures that generated micro-bubbles are fine and uniform in granularity and large in amount by adopting a squirrel-cage type arrangement and a honeycomb micro-fine pore structure and matching with an air inlet manifold; a control valve, a pressure safety valve and a differential pressure transmitter are arranged on the squirrel-cage type self-rinsing micro-bubble generator to ensure that the device is high in degree of automation; a motor drives a rinsing jacket and a rinsing pipe to continuously rotate to sequentially rinse the micro-porous membrane pipe until regeneration so as to finish the self-rinsing operation; the dirt of the micro-porous membrane pipe can be thoroughly cleaned by using the dual-cleaning of the combination of cleaning liquid rinsing operation and gas purging operation; a micro-bubble tank is designed with three closed chambers, namely a rectification chamber, a gas chamber and a steady-flow chamber; moreover, upper and lower division plates are connected with an annular plate by adopting screws, so that the micro-porous membrane pipe can be disassembled and replaced. The whole set of the device is compact in structure, easy in arrangement, operation and maintenance, and low in running cost.