Embodiments of the present invention disclose a method and an apparatus for transmitting a synchronization signal. The method of the present invention includes: determining, by a first terminal, a D2D type, where the D2D type includes D2D discovery and D2D communication; and transmitting, by the first terminal, a synchronization signal according to the determined D2D type. Therefore, synchronization signals transmitted by terminals of different D2D types do not affect each other, avoiding that a second terminal detects and receives a synchronization signal that does not correspond to a D2D type of the second terminal and ensuring that user direct-connection communication can be performed correctly and efficiently.