The avicennia marina crisp biscuits were made of low-gluten flour, powder of avicennia marina, butter, icing sugar and other ingredients. The product processing technology and the formula was optimized by single factor experiment and orthogonal experiment with sensory score as index. The results showed that the optimal formula of the crisp biscuit was: low gluten flour 100 g, butter 50 g, icing sugar 40 g, avicennia marina powder 10 g, salt 0.5 g, whole milk powder 1 g, egg liquid 12 g, baking powder 2 g, water 35 g. According to the above formula, the crisp biscuit with avicennia marina has the advantages of uniform colour, crisp taste, strong fragrance, moderate sweetness and highest sensory score. The hardness is （1 076.0 ± 12.8）g, the cohesion is 0.23 ± 0.01 and the elasticity is（0.2 ± 0.007）mm, the chewiness is （0.8 ± 0.012）mJ.