The invention provides glass powder, positive silver paste, and preparation methods therefor. The glass powder consists of the following components by percentage: 45%-95% of TeO2, 4-40% of Bi2O3, 1-20% of Na2O, 10% of B2O3, ZnO, Al2O3 and SiO2 or less, and 5.5% of LiO2 or less. The positive silver paste comprises the above glass powder. The glass powder is in a Te-Bi-M glass system, wherein M is alkali metal, such as Li, Na, K and so on. The system employs a non-lead compound, thereby achieving the lead-free glass powder, meeting the demands of environment protection, and also improving the applicability of the high-sheet-resistance technology. Therefore, the positive silver paste is prepared through the no-lead glass powder, and can achieve the lead-free glass powder. The methods can effectively increase the sintering temperature through controlling the addition volume of the alkali metal, guarantee the performance stability of a product, improve the weldability and tension force of a grid line, effectively improve the photoelectric conversion efficiency of a silica-based battery, and enables the silver paste to be as good or even better than the positive silver paste in the market currently.