The invention discloses a multi-station collaborative interference positioning method and system based on virtual nodes. The method comprises using three nodes in monitoring nodes as positioning nodes, wherein the RSSI values, receiving the signal of a signal source to be positioned, of the three nodes are the first three maximum values arranged in a descending order, and using the positioning node with the maximum RSSI value as a reference node; determining the coordinates of a second/third virtual node according to the coordinates of the second/third node, a difference between the transmission time from the second/third node to the signal source to be positioned and the transmission time from the reference node to the signal source to be positioned, and the signal receiving direction ofthe second/third node; constructing positioning combinations according to the reference node, one of the second node and the second virtual node, and one of the third node and the third virtual node,and calculating the initial positioning coordinates of respective combinations, calculating the positioning coordinates of the signal source to be positioned according to the initial positioning coordinates and corresponding weighting coefficients. By constructing the virtual nodes, the method enriches the collaborative positioning node combinations, reduces the positioning error caused by node distribution, and improves the positioning accuracy in such a way of weighting the positioning results of different collaborative combinations based on the RSSI values.