The invention provides a process and device for purifying and recovering acetic acid waste liquid. An acetic acid rectifying tower is connected with a rectifying kettle, the rectifying kettle is connected with a tower top primary condenser, the tower top primary condenser is connected with a tower top secondary condenser, the tower top secondary condenser is connected with a reflux ratio controller, the reflux ratio controller is connected with the rectifying kettle, the reflux ratio controller is connected with an acetic acid to-be-detected tank, the acetic acid to-be-detected tank is connected with a front fraction tank, and the acetic acid to-be-detected tank is connected with an acetic acid finished product tank. The bottom of the front fraction tank is divided into two channels, one channel is connected to a middle tank, and the other channel is connected to the acetic acid rectifying tower. By adopting the method, the concentration of the acetic acid with low concentration reaches 98.5% after the acetic acid with low concentration is concentrated, the waste liquid which is difficult to treat originally is changed into industrial-grade acetic acid, and thus, good economic benefits are obtained.