The enzymatic hydrolysis of laver and preparation technology of seafood flavor were studied using Porphyra yezoensis as raw materials. By comparing the hydrolyzing ability of different enzymes and the flavor of hydrolyzates, the best enzyme was screened. The hydrolysis conditions were optimized through the orthogonal experiments using the degree of hydrolysis and sensory evaluation as the reference standard. The optimum hydrolysis conditions were temperature 55℃, time 3h, and the addition of enzyme 3%. Then the hydrolyzate was used to make seafood flavor by the Maillard reaction. With the sensory evaluation as the reference standard, the optimum formulations and optimum conditions of the Maillard reaction were determined through response surface experiments:glutamate 1mg/mL, glycine 0.5mg/mL, cysteine 0.15mg/mL, xylose 8mg/mL, glucose 4mg/mL, thiamine 0.4mg/mL, the reaction temperature 110℃, pH6, and the time 50min. The product showed fine seafood flavor and the flavor was evident. The amino acid composition analysis showed that glutamate and alanine contents were significantly increased in the hydrolyzate. The amino acids in the Maillard reaction were mainly glycine, glutamic, and cystine. About 41 volatile organic components were detected by GC-MS.