The invention discloses a formula of an additive material for polyimide copper clad laminates with high TG. The additive material comprises the following components: aluminium hydroxide powder, dimethyl formamide, magnesium hydroxide powder, polyvinylpyrrolidone, polyvinyl alcohol, calcium hydrate powder and polyacrylamide; the kinds of components of the additive are prepared according to a proper proportion and fused at a high temperature with stirring and mixing. The obtained additive is applied to production process of the polyimide copper clad laminates, on one hand, the type of additive has good compatibility with epoxy resin during usage, on the other hand, the disadvantage of bad toughness due to curing with phenolic resin is overcome, so that the product has good electrical property in a thermal state, and stability of the product is improved at a normal temperature.