A pet excreta treating material made mainly of a ground material of plant origin and having a higher water absorbency in the third measurement than in the first measurement, a water absorbency of 3% to 30% by weight in the third measurement, and a specific gravity of 0.8 to 1.2 measured before the first water absorbency measurement. The water absorbency is measured by immersing a dried excreta treating material in 25° C. water for 3 seconds and calculating the weight increase by the equation below, which is taken as water absorbency (%). In the second and following measurements, the excreta treating material immediately after the preceding measurement is dried and immersed in 25° C. water for 3 seconds to obtain a water absorbency in the same manner.Water absorbency (%)=[(weight of excreta treating material after immersion−weight of excreta treating material before immersion)/(weight of excreta treating material before immersion)]×100.