In this brief, we investigated an approximation-free event-triggered spacecraft formation flying (SFF) controller with prescribed performance. The parameter identification technique is not required in the control scheme, alleviating the computation burden. In addition, the communication burden can be reduced in terms of two aspects: by utilizing the model-free distributed control method, the position of neighbor spacecraft is the only information required to be transmitted; meanwhile, the control input needs to be updated only at the event-triggering instants by employing a event-triggered mechanism. Finally, a numerical example is conducted to illustrate the effectiveness of the proposed controller.