The invention discloses environment-friendly 
flame-retardant heat-conducting glue and a preparation method thereof. The preparation method comprises the following steps: diluting a 
coupling agent by using absolute ethyl 
alcohol, regulating the pH value of the diluted solution, adding a heat-conducting filler, and mechanically stirring; centrifuging, washing, and 
drying, thereby obtaining a component A; uniformly mixing an 
epoxy resin, a curing agent and a curing accelerator by using a high-speed dispersion 
machine, thereby obtaining a low-
viscosity component B; and uniformly 
grinding and mixing the component A, the component B, an 
organic phosphorus flame retardant and aluminum 
hydroxide, vacuumizing, heating the mixture at the temperature of 80-90 DEG C, and heating at the temperature of 130-150 DEG C, thereby obtaining the environment-friendly 
flame-retardant heat-conducting glue. The environment-friendly flame-retardant heat-conducting glue is low in 
viscosity, high in heat 
conductivity coefficient, good in 
mechanical property and high in acid-base resistance and 
corrosion resistance, the flame-retardant level reaches UL94V-0, the heat dissipation problem of a general 
electronic component can be solved; because the heat-conducting glue has good flame-retardant property, when the heat-conducting glue is applied to high-
voltage and high-temperature 
electrical equipment, the on-fire potential safety 
hazard of the 
electronic component is effectively reduced.