Osmotic dehydration is a common pre-treatment method for fruit and vegetable drying. Preliminary studies showed that stachyose could be an alternative to osmotic agents， which yield hot air coupled with instant controlled pressure drop dried（HA-ICPDD） apple chips with uniform porous and crispness. In this study， apple slices were pretreated with stachyose immersion under conditions with different temperature and time water loss（WL） and solids gain （SG）， drying characteristics， microstructure， hardness， crispness， color and total phenols content of the HA-ICPDD apple chips were evaluated. The results showed that， compared with the Deff of those samples with no pretreatment （13.5103×10-9 m2/s）， all the samples exhibited lower Deff （moisture effective diffusivity）， ranging from 8.24128×10-9 m2/s to 12.6321×10-9 m2/s， regardless of the osmotic temperature and time， which could be well fitted by the Page model. The crispness of all the samples significantly increased due to osmotic pretreatments. On the other hand， the color of the samples pretreated with 40 ℃ and 30 min of osmosis were close to the fresh samples. Moreover， no significant decreasing of the total polyphenol contents of the samples was found for the sample pretreated with 40 ℃ for 30 min， compared with those samples with no osmotic treatment. In summary， osmotic treatment at 40 ℃ for 30 min was better condition for stachyose immersion of apple slices， which yield HA-ICPDD apple chips with superior overall quality.