The invention discloses an abrasive flow micropore polishing device, comprising a clamping tool, a base plate, a cavity, a separation device, a laser high-transparency protective lens, a laser, a focusing lens, a flow guiding passage and a one-way valve, wherein the clamping tool is used for clamping a workpiece and locating micropores of the workpiece; the base plate is arranged on the clamping tool; the cavity is arranged in the base plate and the clamping tool and correspondingly communicate with the micropores; the separation device is arranged in the cavity and divides the cavity into a cavitation cavity and a liquid storage cavity; the laser high-transparent protective lens covers the cavitation cavity; the laser can generate laser beams facing to the cavitation cavity; the focusing lens is arranged between the laser and the laser high-transparent protective lens and is used for focusing laser beams in the cavitation cavity; the flow guiding passage can guide deionized water into the caviation cavity; the one-way valve is arranged in the flow guiding passage. According to the abrasive flow micropore polishing device, lasers are focused to cavitate the deionized water to form a large local pressure and impact the separation device, and the abrasive fluid flows and is pushed into the micropores at high speed and rubs the pore walls of the micropores to reduce the roughness of the inner surface of the micropores, so as to achieve the polishing on the micropores. The invention further discloses an abrasive flow micropore polishing process for highly effectively and ultra-precisely polishing the micropores.