Abstract: Disclosed are a halogen-free fire-retardant polyamide composition, and a preparation method and application thereof. The halogen-free fire-retardant polyamide composition is prepared from 35 to 71.5% of a semi-aromatic polyamide, 10 to 35% of a fire retardant and 0 to 50% of an inorganic reinforcing filler, the terminal amino group content of the semi-aromatic polyamide being 80 to 150 mol/t. The halogen-free fire-retardant polyamide composition of the present invention has good heat stability and releases only a small amount of gas in production; mold dirt is not easily formed, and the halogen-free fire-retardant polyamide composition can be produced continuously.