The invention provides a cold fusion reaction tube. The cold fusion reaction tube comprises an outer tube, a mu particle generator, a deuterium atom channel and multiple pairs of exciting electrodes, wherein the mu particle generator, the deuterium atom channel and the exciting electrodes are arranged axially in the outer tube; each pair of exciting electrodes comprises a positive electrode and a negative electrode. According to the cold fusion reaction tube, the mu particle generator, the deuterium atom channel and the exciting electrodes are arranged in the reaction tube, and the characteristics that a seawater concentrated solution contains a large quantity of deuterium atoms and mu particles move rapidly during electrode discharge are used; the deuterium atoms can have a fusion reaction under the cold fusion condition while a reaction environment is not needed to be heated to an ultra-high temperature, the reaction efficiency of the deuterium atoms is improved, the deuterium atoms have the cold fusion reaction quickly in a specific environment, a large amount of heat is released, and conversion of seawater to heat is realized. The conversion is combined with a temperature difference power generation device, so that power generation through seawater is possible, and the cold fusion reaction tube has the great development prospect.