The invention discloses an energy-saving method and system for heat transfer pipe network optimization. The method comprises the following steps that (1), heat supply demands GJ1, GJ2...GJt of all heat supply demand points are acquired; (2), flow original values qa1, qb1...qt1 of all heat transfer pipes are acquired; (3), flow target values qa0, qb0...qt0 of all the heat transfer pipes are calculated; (4), a following data comparison table is formed through calculation, the adjusting number is 1 or m, and m is an integer and is larger than or equal to 2; and (5), the opening quantities of adjusting valves on the corresponding heat transfer pipes are adjusted, and then the heat supply demand of each heat transfer pipe is consistent with the heat supply amount of the heat transfer pipe. According to the method and system, accurate control over the adjusting valves can be achieved, therefore, supply and demand balancing of each heat transfer pipe is achieved, energy sources are saved, andthe cost is reduced.