The invention provides a preparation method and application of a full-nutrition degradable straw seedling raising matrix block. The preparation steps of the matrix block are as follows: 1) the straw is compounded with an active microbial agent and then fermented to obtain plastic silky straw fibers; The nutrient-releasing conditioner is loaded on the carbonized rice husk, air-dried and pulverized to obtain a nutrient-controllable slow-release conditioner carrier; 3) Mix hydrolyzed protein, water, paraformaldehyde, urea, polyvinyl alcohol, and nano-scale functional materials to prepare functional High molecular degradable polymer; 4) Mix plastic silky straw fiber, nutrient-controllable slow-release conditioner carrier, vermiculite, and water, then pulverize, homogenize, and absorb under negative pressure to obtain a straw seedling-raising matrix block, and spray it around The degradable functional macromolecule polymer obtains the matrix block of total nutrition and degradable straw seedling raising; the matrix block can be applied to the dry seedling raising of rice, as well as the seedling raising of landscape grass seeds, cotton, melons and fruits, vegetables, and rapeseed.