The invention discloses an internal-combustion engine cooling system based on an integrative permanent magnet synchronous motor water pump and an electronic speed regulation technology, belonging to the (electronic control) technical field of internal-combustion engine. The internal-combustion engine cooling system can be used for small water-cooled internal-combustion engine cooling systems and can be used for cooling other mechanical, electronic and electrical equipment. The purpose of the invention is to bring simple system, improve cooling control performance and temperature control precision, lower power consumption and obviously improve reliability and practicality. The internal-combustion engine cooling system is characterized in that the internal-combustion engine cooling system comprises a single circulation path cooling circulation system; a permanent magnet rotor operating in a water pump case forms an integrative permanent magnet synchronous motor water pump; the permanentmagnet synchronous motor water pump, a temperature sensor and an electronic speed regulation driving circuit form an automatic cooling control system which can realize required temperature-water pumpflow characteristic and engine body temperature-heat dissipating characteristics and can keep the engine body temperature stable.