This application has disclosed a method for sending and transmission of a resource conflict indication and a communication apparatus. When determining that a reserved resource indicated by first SCI conflicts with a reserved resource indicated by second SCI, a first terminal device sends an RCI to a second terminal device at a determined time domain and/or frequency domain position before a conflict position; or when determining that a resource corresponding to first SCI conflicts with a resource corresponding to second SCI, a first terminal device sends an RCI to a second terminal device at a determined time domain and/or frequency domain position after a conflict position. The RCI is sent at the determined time domain and/or frequency domain position.