Many modern technologies rely on the functional materials that are subject to their phase purity. The topic of obtaining pure crystals from the concomitant allotropes is ever before the eyes of numerous researchers. Here we adopt a template-inducing route and obtain the isolated allotropes located in the appointed regions in the same reaction system. As a typical example, well-defined individual face-centered cubic and orthorhombic ZnSnO3 crystals were successfully synthesized assisted by a ZnO inducing template or without it in an identical solution, respectively. And the different growing mechanisms of the ZnSnO3 allotropes were also proposed, which takes a pivotal step toward the realization of allotropes dividing. Moreover, the two individual pure-phased ZnSnO3 allotropes obtained in one reaction system exhibit porous microspherical morphologies constructed by the tiny nanograins, resulting in their high sensitivities to ethanol with fast response and recovery and good selectivity and stability.