The objective is to obtain a respiratory induction apparatus and a particle beam therapy system in which respiration can appropriately be induced by accurately evaluating the respiration. There are provided a respiratory induction control unit (7cC) that generates a desired respiratory signal (Rtj(t)) for respiratory induction a real respiration measurement unit (7a) that outputs a real respiratory signal (Rrl(t)) obtained by measuring real respiration of a patient and a respiration evaluation unit (7cE) in which by, as a unit, utilizing data of a single period (Tres) of the desired respiratory signal (Rtj(t)), there is calculated a pair of coefficients (a1 and b1), of trigonometric functions, which correspond to the 1st-order terms by means of Fourier series expansion of data of the desired respiratory signal (Rtj(t)) and data of the real respiratory signal (Rrl(t)), which is acquired in synchronization with the data of the desired respiratory signal (Rtj(t)), and there are performed comparisons between the respective gains (Gtj and Grl) and between the respective phases (φtj and φrl), which are obtained from the coefficients (a1 and b1), so that there is evaluated a misalignment of the real respiration from the desired respiratory signal.
