The invention relates to a method and device for recovering isopropylbenzene oxidized tail gas organic matters, residual pressure and afterheat. The device comprises a first heat exchanger, a first stage condenser, a first stage separator, a second heat exchanger, a second stage condenser and a second stage separator which are sequentially connected, wherein an exhaust opening of the second stage separator is connected with a turbo expander inlet sequentially through the second heat exchanger and the first heat exchanger; a turbo expander outlet is connected with the second heat exchanger; a turbo expander is connected with a power generator through a speed reducer. On the precise of ensuring the maximum recovery efficiency of the organic matters, the device sufficiently recovers the afterheat and residual pressure of the tail gas; the maximum comprehensive recovery effect is achieved; the method and the device can be used in a phenol-acetone co-production and epoxy propane production device. The device has the advantages that the trace organic matter loss is small; the afterheat is recovered to the maximum degree. On the other hand, the invention also provides a method for recovering the isopropylbenzene oxidized tail gas organic matters, the residual pressure and the afterheat.