It has been a long history for people to have seaweed, including Phaeophyta, Chlorophyata and Rhodophyta in our dietary, especially in Japan, Korea and some other Aisan countries. Previous studies indicated that having seaweed for a long time would decrease the risk of suffering from cancer and many other diseases. Seaweed is rich in many active substances which are anti-oxidative, anti-bacterial, cholesterolreducing, dietary fiber-increasing, immune system boosting and pH valuemodulating. The potential value of seaweed is very high. Penghu is the area with the maximum quantity of production of natural Porphyra dentata in Taiwan, and the quantity of cultured Porphyra dentata is also quit large. The Porphyra dentata harvested in phase 1 and 2 sells well on the market due to good quality. However, the Porphyra dentata harvested in phase 3 is unsalable due to the bad taste resulting from its bad color, big leaf and crude fiber. The hoarding costs a lot in freezing facility for storing the inferior product. This proposal is to optimize and increase the value of product development to the Porphyra dentata harvested in phase 3 for decreasing the waste of resources, increasing the income of fishermen, and solving the problem faced by the seaweed farmers for many years.