In quantum optics, orbital angular momentum (OAM) is very promising to achieve high-dimensional quantum states due to the nature of infinite and discrete eigenvalues, which is quantized by the topological charge of l. Here, a heralded single-photon source with switchable OAM modes is proposed and demonstrated on silicon chip. At room-temperature, the heralded single photons with 11 OAM modes (l=2~6, -6~-1) have been successfully generated and switched through thermo-optical effect. Such an integrated quantum source with multiple OAM modes and operating at room-temperature would provide a practical platform for high-dimensional quantum information processing. Moreover, the proposed architecture can also be extended to other material systems to further improve the performance of OAM quantum source. This work was published on Laser & Photonics Reviews on September 26, 2022. Doctoral student Shan Zhang is the first author and Professor Feng Xue is the corresponding author.