An inter-stage test structure for a wireless communication apparatus is provided. The wireless communication apparatus has a unit under test (UUT) and a next-stage component connected to the UUT through a signal wire. The inter-stage test structure is disposed on the signal wire and electrically connects the UUT to the next-stage unit component. The inter-stage test structure includes an upper board, a lower board, and an intermediate layer. The intermediate layer is disposed between the upper board and the lower board. The intermediate layer includes a first region and a second region defined thereon. The first region has an air cavity for generating an air impedance. The second region has an impedance adjusting cavity for generating an adjustable impedance. Accordingly, the inter-stage test structure can detect the condition of the UUT of the wireless communication apparatus based on the air impedance and the adjustable impedance.