The invention relates to a road boundary detection and tracking method based on a three-dimensional laser radar. The method comprises the following steps: converting polar coordinate data of a laser radar scanning point into rectangular coordinate data; Extracting ground points by using a random sampling consistency plane fitting method and a principal component analysis method; Roughly extractingroad boundary feature points by adopting a multi-feature, wide-threshold and hierarchical feature point extraction method; Dividing the roughly extracted road boundary feature points into a left roadboundary feature point and a right road boundary feature point by using a projection-based method by referring to the idea of linear discriminant analysis; Respectively filtering the left road boundary point and the right road boundary point by using a random sampling consistency method to obtain final road boundary points; Fitting the left road boundary line and the right road boundary line by adopting a quadratic polynomial random sampling consistency method; And tracking the road boundary line by adopting a Kalman filtering method based on amplitude filtering. The method can be used for processing various complex scenes and working conditions, and can be widely applied to unmanned driving.