The　molecular　traffic　control　(MTC)　effect,　a　critical　concept　in　porous　materials　catalysis,　describes　the　diffusion　behavior　of　reactant　and　product　molecules　through　pore　channels　within　zeolites,　thereby　establishing　a　relationship　between　the　pore　system　and　the　catalytic　performance.　Herein,　a　series　of　a-oriented　MFI-type　ZSM-5　catalysts　with　modulated　orientation　length　while　maintaining　comparable　physicochemical　properties　are　synthesized,　and　their　performance　in　butene　cracking　reactions　are　evaluated.　By　precisely　modulating　the　pore　structure　and　crystal　morphology　of　ZSM-5,　it　is　demonstrated　that　minimizing　the　sinusoidal　channel　length　along　a-axis　effectively　optimizes　the　MTC　effect,　resulting　in　a　superior　propene　selectivity　(≈60%)　and　an　enhanced　propene-to-ethene　ratio　(≈12).　Computational　simulations　coupled　with　experimental　measurements　reveal　that　reducing　the　length　along　a-axis　facilitates　preferential　outward　diffusion　of　propene　molecules　as　terminal　products.　This　work　not　only　provides　solid　proof　of　molecular　traffic　control　but　also　offers　theoretical　guidance　for　the　rational　design　of　other　useful　porous　catalysts.　©　2025　Wiley-VCH　GmbH.