In　this　work,　ZnO　hollow　spheres　(ZnO-HS)　with　mesoporous　shells　were　successfully　synthesized　via　a　facile　two-step　method.　The　hollow　structure　provides　sufficient　space　and　active　sites　for　adsorbing　gases.　The　mesoporous　shells　assembled　from　nanoparticles　facilitate　the　diffusion　of　gas　molecules　into　the　inner　space　and　ensure　full　contact　with　ZnO.　Consequently,　ZnO-HS-600　gas　sensors　deliver　a　satisfactory　response　to　volatile　organic　compounds　(VOCs)　and　an　excellent　response-recovery　time　at　the　optimal　working　temperature　of　300　degrees　C,　i.　e.,　acetone　(9　and　5　s),　ethanol　(10　and　6　s),　and　methanol　(12　and　14　s),　respectively.　By　combining　the　theoretical　calculation　and　the　experimental　observation,　the　relationship　between　the　structure　and　performance　has　been　established.　The　results　demonstrate　that　ZnO-HS-600　materials　meet　the　regional　depletion　condition,　i.　e.,　L　＞=　2L(s),　further　explaining　its　superior　response-recovery　time.　Our　work　provides　a　prospective　strategy　for　high-performance　ZnO　gas　sensors　via　structural　design　and　theoretical　calculations.