The invention discloses a non-ironing triple-proof finishing method of ready-made garments, which comprises the steps of S1, preparing a non-ironing pre-finishing agent and a non-ironing post-finishing agent, and foaming the non-ironing post-finishing agent; S2, spraying the non-ironing pre-finishing agent evenly to the front; S3, pre-drying; S4, carrying out pressure ironing; S5, carrying out baking setting; S6, applying foam of the non-ironing post-finishing agent to the back; and S7, drying. The non-ironing pre-finishing agent is made with organic fluorine-modified acrylic resin, an anti-wrinkle non-ironing finishing agent, a fiber protectant, a triple-proof aid, a softener, a penetrant, a catalyst and polyacrylate powder; the non-ironing post-finishing agent is made with styrene-modified polymethyl acrylate, an anti-wrinkle non-ironing finishing agent, modified polyester fibers, polyamide fibers, a softener, a penetrant, a foaming agent, alkyl polyglucoside, and fatty acid methyl ester sulfonate. The non-ironing triple-proof finishing method herein has the advantages that non-ironing finishing can be provided for ready-made garments, and the ready-made garments can wick moisture and dry fast, can repel water and oil, can prevent pollution and can inhibit bacteria for long time.