Box-Behnken design and response surface methodology were employed to optimize the steam explosion process of peanut shell. The microstructure of peanut shell before and after blasting was observed by SEM. Luteolin was further purified by AB-8 macroporous adsorption resin and subsequently analyzed by FT-IR and HPLC, while quantified by UV-Vis spectrophotometry method. The results showed that the optimal steam explosion pressure was 1.25 MPa, and the optimal residence time was 46.0 s, with optimal water content of 16%. Under these conditions, the yield of luteolin was 0.926%, which was 1.9 times that of the untreated peanut shell. The SEM microphotographs showed that the surface layer of peanut shell was broken by the pretreatment of steam explosion, while the lattice-like structure in the shell was removed with the cellulose macro fibers floating above the surface in a smooth pattern. After steam blasting, the content of luteolin in the purified product reached 32.81%, which was much higher than that of the unexploded product. The extraction rate of luteolin from peanut shell extract was significantly increased by steam blasting pretreatment.