The invention relates to a method for preparing a light, thin, heat-insulating and flame-retardant plush fabric. The method comprises the steps of weaving a fabric, wherein terry yarn is 98% of 32S/1 aramid fiber 1313 / 2% of conductive filament, and connecting yarn is 100D/36F polyester flame-retardant double-sided plush; causing the fabric to undergo dyeing, drying, soft forming, galling, intermediate shaping, combing, shearing and final shaping, and obtaining the light, thin, heat-insulating and flame-retardant plush fabric. The method is short in process and good in stability, the obtained plush fabric insulates heat, is light and thin, has an outstanding flame-retardant effect, does not melt, has no melting drip and does not generate smoke, the afterflame time is 0 s, the smoldering time is 0 s, the plush fabric is permanently resistant to flame and is comfortable to wear and soft in touch, the final finished knitted fabric gram weight is 271 g/m2, the heat-insulating value CLO is 0.5-1.0, and the plush fabric has good application prospects.