Disclosed is a filler of a sealant a filler of a sealant and a method for manufacturing the same and a composite sealant. The filler of the sealant includes a filling material and a catalyst wrapped around the filling material. The catalyst includes a material provided to melt and generate a thermal reaction when a predetermined temperature threshold is exceeded. The predetermined temperature threshold is a minimum temperature at which the sealant is subject to thermocuring. A melting point of the filling material is higher than a maximal temperature during the thermocuring of the sealant. In the filler of the sealant, it is not necessary to change an initial composition and content of the sealant, the catalyst wrapped around the filling material is heated, and then melts and generates a thermal reaction to accelerate curing efficiency of the sealant during a thermocuring of the composite sealant. Therefore, a curing time of the composite sealant is shortened and a risk of liquid crystals to be contaminated is decreased.