The present invention features a sustained-release microcapsule for long-term pest controlling. In general, a microcapsule has a capsule core including active pest-control ingredients and diluents, and a capsule shell which physically separates the capsule core from the surrounding medium. Diluents are arranged to entrap active ingredients therein and to provide resistance to mass transfer of the active ingredients therethrough. The capsule shell generally includes the shell pores and provides additional resistance to mass transfer of the active ingredient therethrough. Diluents are selected from a class of material such that the mass transfer resistances existing in the capsule core and/or capsule shell depend on the temperature of the surrounding medium.