The invention discloses a driver alertness monitoring method based on electroencephalogram information. The method comprises the steps that 1, an electroencephalogram sensor is used for collecting an original electroencephalogram signal of a driver; 2, noise-reduction and artifact removing treatment is conducted on the original electroencephalogram signal to improve the reliability of the electroencephalogram signal; 3, correlated alertness characters including the time-space character, the spectral character and the complexity character are extracted; 4, the correlated alertness characters are filtered to remove signals which have nothing to do with alertness states; 5, the relation between the extracted electroencephalogram characters and the alertness states of the driver is found out, and estimation on the alertness states of the driver is eventually achieved by utilizing the extracted electroencephalogram characters. By means of the driver alertness monitoring method based on the electroencephalogram information, the alertness states of the driver can be obtained most objectively and accurately, and enormous potentiality is shown in the field of driving fatigue monitoring. The invention further provides a driver alertness monitoring system based on the electroencephalogram information.