As the dominant allergen in peanut， Ara h 1 has a relatively high allergenicity among peanut allergens. According to the previous researches， methods used for Ara h 1 purification usually involve with two or three steps of chromatography， which is tedious and costly. In this study， pET-32a-Ara h 1 plasmid was constructed and Escherichia coli BL21（DE3） pLysS was utilized for recombinant Ara h 1 expression. Ni-NTA affinity column and gradient elution were used for purification. MALDI-TOF MS and western-blot were used to identify recombinant Ara h 1 and analysis its sensitivity respectively. According to the results， the sequence of Ara h 1 in the plasmid was consistent with the gene data of Ara h 1 in the NCBI database. When 300 mmol/L IPTG（isopropyl-β-D-thiogalactopyranoside） was added and cells were cultured at 22 °C for 22 h， the yield of recombinant protein is at a relatively high level. After adding 15 mmol/L sodium laurylsulfonate to the lysis buffer， the recombinant protein could be effectively released to the supernatant. The elution buffer containing 50 mmol/L and 100 mmol/L imidazole were used in the elution process. Recombinant Ara h 1 with high purity and immunoreactivity could be obtained by using the method above.