Disclosed are a physical downlink control channel transmission method and apparatus, which are used for achieving, in the case where an initial signal or signalling which indicates an initial position of a physical downlink shared channel is not transmitted, a method in which a physical downlink control channel is used for transmitting and indicating an initial position of a physical downlink shared channel. The method comprises: a terminal determining, according to each candidate time position in a set of candidate time positions and a set of candidate physical downlink control channel/enhanced physical downlink control channel resource positions corresponding to the candidate time position respectively, a physical downlink control channel/enhanced physical downlink control channel bearing downlink control information in an unauthorized frequency band wireless frame; and the terminal receiving the downlink control information by means of the determined physical downlink control channel/enhanced physical downlink control channel.