Blue print paper and preparation method thereof

The invention provides blue print paper and a preparation method thereof. The blue print paper comprises the following ingredients: bleached chemical softwood pulp, bleached chemical hardwood pulp and mechanical wood pulp; the blue print paper consists of a surface layer and a bottom layer; the surface layer adopts the fiber proportion in part by weight: 30 percent of bleached chemical softwood pulp, 45 percent of bleached chemical hardwood pulp and 25 percent of mechanical wood pulp; the bottom layer adopts the fiber proportion in part by weight: 30 percent of bleached chemical softwood pulp, 25 percent of bleached chemical hardwood pulp and 45 percent of mechanical wood pulp; the blue print paper has the characteristics of convenience for use, clear pattern, durability and low cost.