The invention discloses a tomato seedling cultivation substrate. The tomato seedling cultivation substrate comprises raw material components of corn straw compost products and mushroom residues. According to the tomato seedling cultivation substrate, corn and the mushroom residues serve as raw materials and accordingly the environment-friendly effect is achieved, the pollution is avoided, the resources are saved; the requirements for nutrition in the tomato seedling stage are met and the substrate hardening is not caused; root systems of tomatoes cultivated through the tomato seedling cultivation substrate are developed and the formation rate and the quality of plug seedlings are high; the rate of seedling emergence of the tomatoes is high, the seedlings are neat, and the growth is consistent; the tomato seedling cultivation substrate can be applied to the tomatoes and can also be applied to other crops and accordingly the application prospects are broad. A production method of the tomato seedling cultivation substrate is simple and convenient to operate.