The flame retardant F-ATP was prepared by surface modification of attapulgite (ATP) with fischer-tropsch wax (FTW). The morphology, structure and thermal stability of the flame retardant F-ATP were characterized. The results showed that the aggregation of the modified ATP disappeared and its thermal stability was significantly improved. The flame retardant F-ATP was added to poly (terephthalic acid/butylene adipate) (PBAT) matrix to prepare PBAT/F-ATP composites. The LOI, UL-94, CCT, FTIR-TG, raman spectroscopy and SEM were used to analyze the flame retardancy property of PBAT/F-ATP composite. The results showed that when adding 10 wt% flame retardant F-ATP, the flame retardancy property of PBAT-3 composite was the best, where its LOI value and UL-94 grade reached 23.5% and V-1 grade, and the droplet phenomenon was greatly improved. In addition, compared with the composite including 10wt% ATP, the PHRR and THR values of PBAT-3 composites decreased by 4.99% and 26.11%, respectively. At the same time, the TG-IR results showed that the release of gaseous products of PBAT-3 composites decreased in the whole combustion process, which had a good gas phase flame retardant effect. The outstanding flame retardant property was mainly due to the addition of flame retardant F-ATP, where the PBAT/F-ATP composites formed a dense and continuous carbon layer, which effectively insulates the heat/mass transfer between the interior and exterior of the PBAT/F-ATP composite.