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ZSM-5 zeolite microparticles (MPs) were synthesized under hydrothermal condition using a low crystal seed addition approach without template. The synthesis parameters such as the seed addition amount, the SiO2/Al2O3 ratio, the aluminum source, the feeding addition method, aging, and crystallization were investigated. The structure, morphology and composition of the as-synthesized ZSM-5 zeolite MPs were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), laser particle size distribution (PSD) measurements, and inductively coupled plasma-atomic emission spectrometry (ICP-AES). The SiO2/Al2O3 ratio of ZSM-5 zeolite MPs was in the range of 20-80. The low seed addition was beneifcial to improving the crystallinity and shortening the crystallization time, and the suitable amount of seed was 0.25% (SiO2). The ZSM-5 zeolite MPs synthesized with aluminium nitrate nonahydrate used as the aluminum source exhibited a relatively high crystallinity. An appropriate aging time could eliminate the effect of feeding addition method and effectively adjust particle size. The particle size of ZSM-5 zeolite obtained at an aging time of 20 h was around 2.0 μm. Prolonging the aging time appropriately could also shorten the high-temperature crystallization time. The suitable aging time was 24 h, and the relative crystallinity of ZSM-5 zeolite could reach up to 99% after crystallization for 24 h at 180℃.