In order to optimize the process conditions of microwave puffed sweet potato chips, the orthogonal test design method was used, the main factors were sweet potato varieties, slice thickness, initial water content, blanching time, microwave intensity and puffing time, and the evaluation indexes were color, puffing rate, fracture strength and sensory score. The results showed that sweet potato varieties, slice thickness, initial water content, microwave intensity and puffing time were the main influencing factors. The optimum technological conditions for microwave puffing sweet potato chips were as follows: variety “Shandong purple potato”, longitudinal section thickness 2.0 mm, blanching 180 s with boiling water, water content 15%, microwave intensity 2.3 W/g, puffing time 50 s; variety "Fujian yellow heart", longitudinal section thickness 2.5 mm, blanching 180 s with boiling water, water content 15%, microwave intensity 2.3 W/g and the puffing time 50 s. The sweet potato chips obtained under the process conditions had good color, taste and texture, and puffing effect, which provided an effective reference for the development and utilization of sweet potato and the improvement of the quality of sweet potato chips.