This paper investigates the indoor communication of radio waves carrying orbital angular momentum (OAM) inside a rectangular corridor, that has electrical conducting walls. The method of moments (MoM) is employed in this study for the modeling of a uniform circular array (UCA) and a rectangular corridor. The UCA consists of eight dipoles and a reflecting ground. A transmitting UCA (Tx) and a receiving UCA (Rx) are located at two ends of the corridor. Standard scattering parameters are exported from the full-wave simulation and further used to calculate the wireless communication between Tx and Rx using mixed modes. Comparing to the free space case, the possibility of indoor wireless communication of OAM waves is investigated. Specifically, the transmission of different OAM modes with regard to communication distances and location is numerically explored.