The invention provides a method for preparing porous water collection sponge bricks from light-emitting phosphorus absorption type tomato straw extruded particles. The method comprises the following steps of preparing materials of the porous water collection sponge bricks: sampling and uniformly mixing 15-20wt% of cement, 45-65wt% of modified tomato straw extruded particles of which the particle size is 250-450 [mu]m, 5-15wt% of sodium silicate of which the modulus is 3.2-3.5, 3-5wt% of calcium oxide of which the particle size is 100-200 [mu]m, 3-10wt% of polyester fibers, 0.5-5.0wt% of high-water-absorption resin fibers, and 15-30wt% of activated carbon of which the particle size is 100-150 [mu]m; performing slurry mixing according to a water-cement ratio being 0.4-0.7, and then adding aluminum powder paste which is 0.2-1.5% of the total weight of mixed materials; enabling the aluminum powder paste to be subjected to a hydration reaction to obtain bubbles and porous expanded water absorption slurry, uniformly stirring the slurry, and pouring the uniformly stirred slurry into a test mold of a sponge brick pressing machine; and performing scrapping, performing pressing, performing demolding, and performing airing so as to obtain the sponge bricks.