In order to explore the relative humidity on the water loss rate of wheat starch/gluten-based product， in this study， starch-rich component (starch) and protein-rich component (gluten) which are the main components of wheat noodles were set as the test objects. The starch/gluten mixture was designed according to starch account for 100%， 90%， 50%， 25% and 0%. Three physical models of different relative humidity of environment and water activity of samples were set by adjusting relative humidity. The differentia values of relative humidity of environment and water activity of samples were gradually decreased (22%-2%)， basically unchanged (22%-22%)， increased by degrees (22%-37%). Water loss rate was analyzed under the three models. The result showed， under the three models of decreased， constant and increased， the water loss rate of powder with starch content of 100%， 90%， 50%， 25%， 0% were 2.26×10-3-6.41×10-3， 2.20×10-3-6.83×10-3， 3.06×10-3-7.39×10-3， 3.74×10-3-6.79×10-3， 4.31×10-3-7.15×10-3(mg/mg water content)/min. In conclusion， the water loss rate of wheat starch/gluten blend powders was gradually increased with increased water activity of sample and relative humidity of environment difference. The average water loss rate of gluten powder (0% starch content powder) was higher than starch (0% gluten content powder). As starch content gradually increased， or gluten content decreased by degrees， it showed a gradually decreased trend of the average water loss rate of the blend powder on the whole.