Abstract: Environment-friendly flame retardants, cyclotriphosphazene derivatives, were synthesized and characterized by IR spectra and 31P-NMR, and proved that the cyclotriphosphazene (HCCP) was substituted with pentaerythritol (PER). The influence of ratio of raw materials, solvent and reaction time were systematically investigated. The optimal reaction conditions were determined as n(HCCP)∶〖KG-*2/3〗n(PER)=1∶〖KG-*2/3〗5, tetrahydrofuran as solvent, reaction for 24 h, and the yield was up to 7645%. Vertical combustion method was used to test the flame retardant properties of the flame retardant, the results show that continued burning time and smoldering time are 0 s when the concentration of flame retardants was up to 30% and the char yield 40%. In order to improve the adhesion of the flame retardants in textiles, mixed environment-friendly flame retardants and silicone acrylic emulsion were applied on cotton fabrics finishing. Based on the trends of scrub-resistant performance and the retardant properties of the sample, the best ratio of flame retardants and silicone acrylic emulsion was 3∶〖KG-*2/3〗7.