Concerning that current automatic delimitation of land border dispute areas neglects some important factors, this essay puts forward a new automatic generation method of land delimitation line based on parallel simulated annealing algorithm. Firstly, "point-point" topological relationship is built up based on terrain line network and disposed according to delimitation laws. Secondly, coding and estimation of delimitation line is needed for simulated annealing algorithm, as well as generation of initial delimitation line. Thirdly, parallel simulated annealing algorithm need to combine different ways of annealing to search for the best delimitation line fast and fully. The experiment shows that this method can not only take area ratio decided by related countries, terrain and special areas into account, but also ensure that one could get the biggest resource profit, which can protect its delimitation profit in a better way.