Evaluation of the cut quality is extremely significant to industrial applications of laser cutting. The relationship between cut quality and processing conditions has been investigated by using one of the measurable cut qualities, such as kerf width, striations, dross, roughness and so on. However, each of these qualities can only partially represent the cut quality. In this paper, a synthetic evaluation method for laser cutting quality has been proposed. A 3KW CO2laser was used to perform cutting experiments with 1.0mm thick mild steel sheets. The cut quality indicators, including kerf width, striations, dross, roughness, under different cutting conditions have been studied. A Synthetic Quality Number (SQN) has been presented as the evaluation indicator by quantitatively analyzing the conventional indicators. A neural network based method to anticipate laser cutting quality has been presented with SQN as the evaluation indicator.