Apple slices were treated with different processes such as with and without hot water blanching before freezing, normal temperature and pressure plate freezing, vacuum freezing, slow thawing at 20 ℃, and quick thawing at 50 ℃, then apple slices were all treated by vacuum-freeze. The comparative experiments and analysis showed that heat-blanching before freeze-thawing significantly increased water loss rate in vacuum freezing groups, the thawing juice loss rate in plate freezing and vacuum freezing groups, increased the relative conductivity of the secondary frozen apple slices, and significantly reduced the color difference of the secondary frozen apple slices (p<0.05). During freeze-thawing treatment, the water loss rate in plate freezing groups was about 4%, but in vacuum freezing groups was about 40%, and the thawing juice loss rate in plate freezing group was significantly higher than the vacuum freezing groups. During the second time vacuum freezing, the water loss rate and the relative conductivity in the plate freezing groups were significantly higher than those in vacuum freezing groups. The combined method of hot water blanching, vacuum freezing, thawing at 50 ℃ and secondary vacuum freezing resulted in the highest total mass loss rate of 76.10%. Considering the experimental results, the combined method of hot water blanching, vacuum freezing, thawing at 20 ℃ and twice vacuum freezing was the best with higher water frozen loss rate during freezing, lower thawing juice loss rate and little color change.