The invention provides a sewing state monitoring system of a sewing machine and the sewing machine including the sewing state monitoring system. The sewing state monitoring system includes a sewing thread tension detection sensor and a controller, the sewing thread tension detection sensor is used for detecting the tension of a sewing thread and sending a tension detection electric signal to the controller, the controller receives and monitors the tension detection electric signal, and according to the presence or absence of hook line pulse and/or pick line pulse, whether the sewing machine has skipping stitch and/or line breaking phenomena or not is judged. According to the provided sewing state monitoring system, the tension change of the sewing thread is converted into electrical signalchange of a sensor, and the controller thus easily carries out monitoring and judgement.