This investigation proposes to adopt proper orthogonal decomposition (POD) to inversely design multiple air-supply parameters based on the specified design targets. The method first sampled some thermo-flow data by full CFD simulations, and then the orthogonal spatial modes and their coefficients are extracted. The above method was applied to design the air-supply opening size, air-supply direction and temperature in a three-dimensional cabin with the constraint of a fixed ventilation rate. The results show that the proposed method is able to efficiently determine the air-supply temperatures and directions simultaneously.