Abstract: In this paper, we took the sensory evaluation and the recovery ratio of amino acid and nitrogen as evaluating indicator.Then we got the optimal condition that the addition of lyophilized lemon peel powder was 4%, p H was 4, deodorization time was 50 min, and the deodorization temperature was 30 ℃, based on single factor experiment combined orthogonal experiment to investigate the deodorization of lyophilized lemon peel powder for enzymatic hydrolysate of Mactra veneriformis.The volatile components of lyophilized lemon peel powder were determined by headspace solid phase microextraction combined with gas chromatography-mass spectrometry ( HS-SPME-GC-MS) . The results showed that 54 kinds of substances were detected in the enzymolysis solution before deodorization. Among them, 1-octen-3-ol and nonanal were the main smell substances, and 42 substances were detected in the enzymolysis solution. The odorant was limonene and other pleasant odor components.The dominant volatile components and the increased components in the hydrolysate after the deodorization were aroma substances and they were from the freeze-dried lemon peel powder.The results showed that the lemon peel powder had masking effect on the smell of the hydrolysate.