Propane aromatization on metal‐modified zeolites provides a promising route to produce valuable chemicals such as benzene, toluene and xylene via non‐petroleum feedstocks. The mechanistic understanding of propane conversion to aromatics is still challenging due to the complexity of the aromatization process. Herein, by using solid‐state NMR spectroscopy and GC‐MS, it is shown that cyclopentenyl cations are formed as active intermediates during propane aromatization on Ga/ZSM‐5 zeolite. Autocatalysis of propane to aromatics is identified in the induction period. The cyclopentenyl cations serve as key hydrocarbon pool species to co‐catalyze propane conversion and promote aromatics formation, revealing a dominant hydrocarbon pool process in propane aromatization.