The invention discloses a high-pressure boiler feedwater treatment system which comprises a first water tank, a combined filtering device, a reducing agent adding device, a scale inhibitor adding device, a precision filter, a first high-pressure pump, a reverse osmosis host, a carbon dioxide degassing tower, a second water tank, an ion exchange mixed bed, a third water tank, a second high-pressure pump and a fourth water tank, wherein the first water tank, the combined filtering device, the reducing agent adding device, the scale inhibitor adding device, the precision filter, the high-pressure pump, the reverse osmosis host, the carbon dioxide degassing tower, the second water tank, the ion exchange mixed bed, the third water tank, the second high-pressure pump and the fourth water tank are connected sequentially through a water pipeline. Through the way, the system disclosed by the invention has low cost, and the produced desalted water can sufficiently meet the requirements of the industry.