We developed a high-resolution accurate mass (HRAM)-LC-MS/MS method using the same food extract used in the ELISA method and an MS sample preparation kit. Multiple food allergen analysis was performed using 1, 5, 10, and 20 ppm of allergen-incurred processed foods. Overall, a strong correlation was observed between the measured values of HRAM-LC-MS/MS and ELISA, demonstrating the applicability of multi-allergen analysis using LC-MS.