The invention provides a Terahertz multiple pulse transient state time domain spectrograph and is aimed at solving a technical problem that a time domain spectrograph of the prior art cannot be used for subjecting Terahertz detecting pulses to multiple continuous times of transient measuring operation. According to the spectrograph disclosed in the invention, femtosecond laser generated by a femtosecond laser generation module is transmitted to a beam split delay module, a first femtosecond pulse sequence and a second femtosecond pulse sequence are generated, an inclined leading edge pulse sequence is generated after the first femtosecond pulse sequence is processed via an inclined leading edge pulse sequence generation module, a Terahertz pulse sequence is generated after the second femtosecond pulse sequence is processed via a Terahertz pulse sequence generation module, the inclined leading edge pulse sequence is transmitted to an optical spectrum obtaining module after being modulated via the Terahertz pulse sequence in a pulse sequence modulation module, waveform information of the Terahertz pulse sequence carried by the modulated inclined leading edge pulse sequence is obtained by the optical spectrum obtaining module, and therefore Terahertz multiple pulse transient state time domain optical spectrums can be measured.