The invention discloses an air suction device of a spandex spinning corridor and a process thereof. The air suction device is additionally arranged near the silk outlet of the spinning corridor. The air suction amount of each spinning position is 5-15 Nm3/h. The air sucked in from the silk outlet is separated separately and processed respectively. Therefore, the exhaust gas suction amount is reduced; the exhaust amount is reduced; the oxygen content of the exhaust gas is decreased; the nitrogen replacement amount is reduced; the exhaust gas recycling amount is increased; and the environmentalprotection target of energy conservation, emission reduction and low-carbon production is further achieved. The air suction device comprises a corridor cylinder body, an air suction cavity body, air suction holes, an air baffle plate and an air suction flange interface. The air suction cavity body is in the shape of a rectangular cross section, surrounds the outer wall of the corridor cylinder body and forms a closed air suction cavity together with the corridor cylinder body; and the corridor cylinder body surrounded by the air suction cavity body is provided a plurality of rows of air suction holes which are distributed along the circumference. The air suction flange interface is communicated with the air suction cavity; the air baffle plate in the shape of a circular section is arranged in the air suction cavity near the air suction flange interface; and the center of the air baffle plate is aligned to the axial lead of the air suction flange interface.