The invention discloses an efficient lane line detecting and tracking method and a system. The method comprises the following steps: S1, collecting vehicle environment image information; S2, determining the position of a vanishing line, a region of interest, and the maximum and minimum values of width of a matching lane line; S3, carrying out edge detection, and searching for feature points meeting the lane line feature search conditions; S4, projecting the feature points meeting the lane line feature search conditions to the vanishing line and two preset lane horizontal lines, and finding a vanishing point on the vanishing line; S5, carrying out reverse search according to the position of the vanishing point, extracting the feature points of a lane boundary line, and determining a lane line; and S6, building a band region according to the lane line, and restraining the position and width of the lane line with use of confidence. According to the invention, a vanishing point is detected based on a voting mechanism, a target search area is divided, and a lane line can be detected quickly and accurately by collecting two points on the lane edge line.