The invention relates to a tobacco flake quality control method and system based on loosing and conditioning. The method comprises the steps of selecting outlet moisture and hot air temperature as factors influencing the loosing and conditioning quality, and collecting statistics on the quality data of the outlet moisture and the hot air temperature; establishing a water adding valve feed-forward control model and a hot air temperature subarea feedback control model based on outlet moisture and material flow from the statistical results according to the quality data of the outlet moisture and the hot air temperature; and controlling the outlet moisture and the hot air temperature respectively according to the water adding valve feed-forward control model and the hot air temperature subarea feedback control model, thereby realizing online control of the loosing and conditioning key quality characteristics. By adopting the method and the system, the quality characteristic indexes of the original shredding procedure can be greatly improved, the capability of the loosing and conditioning process for overcoming and eliminating abnormal interference is enhanced, the capability of the process is improved, the stability of the hot air temperature and the outlet moisture in loosing and conditioning is sufficiently guaranteed, full automatic control is realized, the labor intensity is relieved, and the product quality is improved.