The invention is applicable to the field of an integrated circuit and provides a radiation-proof ultrahigh-speed triggering circuit and a spaceflight ultrahigh-speed trigger. The radiation-proof ultrahigh-speed triggering circuit comprises a first sensitive amplifier, a second sensitive amplifier, a logic gate circuit and an RS (reset-set) latch, wherein the first and second sensitive amplifiers have double interlocking structures, data is stored into different nodes through two-way interlocking, the logic gate circuit carries out SEU (single particle upset) interference resistance processing on data in different nodes, and generates pre-charging signals, setting signals or resetting signals, the RS latch with a crossed coupling structure forms a phase inverter pair structure when receiving the pre-charging signals for realizing the data latching, or the output time delay avoidance is realized through a symmetrical structure during setting signal or resetting signal receiving. The radiation-proof ultrahigh-speed triggering circuit and the spaceflight ultrahigh-speed trigger have the advantages that the two sensitive amplifiers adopting the DICE structures are used as the front stage of the trigger for preventing the SEU influence, in addition, the front stage output is output to a later stage of RS latch through the logic gate operation, the ascending and descending edge difference-free output is realized through the two symmetrical RS latches with the crossed coupling structures, and the functions of high-speed data transmission is realized.