For finding on the new function of the product Yeast Mannan (Man) which made in our ADFLab and it is from the wasted beer yeast of the beerfactory. We did more research about the structure, property and the bioactivity of the Man. And then, we modified the structure of the Man by sulfated to get new product sulfatedMan (Mansulfated). The results show that the Mansulfated had some new bioactivity, which: 1) is no cytotoxin for the host C8166 cells which belong to human T lymphocyte system; and 2) can inhibit the virus of HIV1 cell growing in vitro. But the experiment results also show that the degree of the inhibit to the HIV1 virus cell growing by the Mansulfated is relation with the kinds of sulfated regents and the experiment methods, temperature, and cause effect of modified structure and construction of Man in different degree and then to produce differential biological function of Mansulfated product.