The invention discloses a heat-pipe circulating type primary refrigerant loop server cabinet heat dissipation system, which comprises more than one heat pipe radiator, a server cabinet, a refrigerant loop fluorine supply branch pipe, a refrigerant loop fluorine return branch pipe, a machine room refrigerant loop fluorine supply main pipe, a machine room refrigerant loop fluorine return main pipe, a reservoir, a maintenance ball valve, an outdoor fluorine supply connecting pipe, an outdoor fluorine return connecting pipe, a heat exchange coil fluorine supply pipe, a heat exchange coil fluorine return pipe, a fluorine supply valve, a fluorine return valve, a closed cooling tower, a control module and the like. The precise short-distance transport of cold air of the cabinet is realized, and the problems that the server cabinet is locally overheated and has heat points are solved; meanwhile, a natural cooling measure is utilized, the heat exchange temperature difference is large and the efficiency is high, and the active anti-condensation and flow protection control are adopted. The heat dissipation system has the characteristics of high reliability, low power consumption and low noise, and meets energy saving and environment-friendly ideas.