An apparatus and a method is provided for detecting biometric signals of a driver and classifying the driver into a normal state or a fatigued state based on the biometric signals. An apparatus may include: a biometric signal measuring part configured to measure the biometric signals including a blood flow rate of a brain of the driver using an electro-encephalography (EEG), an electro-cardiography (ECG), and a functional near-infrared spectroscopy (fNIRS) of the driver; a biometric signal integral part configured to integrate the measured biometric signals, to extract characteristics of the respective biometric signals from the measured biometric signals and to then integrate the extracted characteristics, or to classify the extracted characteristics of the biometric signals and to then integrate the classified characteristics; and a driver state detecting part configured to detect the state of the driver based on the integrated biometric signals.