The invention discloses a node positioning method based on pseudo random code correlation detection, wherein the node positioning method is used for realizing accurate positioning of a node in a wireless sensor network. The method comprises the steps of 1), measuring a distance between node pairs in a wireless sensor network based on an ultrasonic wave pseudo random code TDOA detection method; 2) constructing a node spatial distance matrix, and for the node pair of which the distance is not measured, performing processing by means of an Eculidean and shortest path fusion method; 3), performing processing on the spatial distance matrix of the nodes for obtaining a spatial relative coordinate system of all nodes; and 4), converting the spatial relative coordinate systems of all nodes into absolute coordinates by means of a planar conversion model. According to the node positioning method, an ultrasonic signal which is transmitted by the node is coded by means of pseudo random code related detection technology, thereby effectively improving distance measuring range and measurement precision of the nodes. A simulation experiment result proves a fact that the node positioning method can realize higher positioning precision and relatively low positioning error on the condition of different network scales and different distance measuring errors.