Objective: To identify the alkaloid compounds of Aconite Lateralis Radix and to probe into the dynamic changing regularities of main constituents during decoction process. Method: HPLC-Q-TOF-MS was used to identify chemical constituents and to analysis the content changes of main constituents during decoction process using dissolution rate. Result: Totally 36 alkaloid compounds of Aconite Lateralis Radix were identified and the dissolution rates of 25 compounds were determined in the process of decoction. The results showed that diester alkaloids (mesaconitine

hypaconitine

aconitine and deoxyaconitine) decreased quickly and their content were not detected after decocting 2 h;monoester alkaloids (benzoylaconine

benzoylmeaconine

benzoylhypaconine

10-OH benzoylmeacinine

benzoyldeoxyaconine and dehydrated-benzoylhypaconine) firstly increased and reached the peak in 6 to 8 h and then gradually deceased. Aconine alkaloids (mesaconine

aconine and hypaconine) increased all the time during decoction process. General alkaloids firstly increased and reached to the peak in 6 to 8 h and then tended to stability. Conclusion: The analysis of the alkaloid compounds of Aconite Lateralis Radix was comparatively comprehensive and the dynamic changing regularities of the alkaloid compounds were explored. It provided a reference for quality control and clinic application of Aconite lateralis Radix.