The invention provides a method for measuring key parameters of VOC (Volatile Organic Compounds) emission in an in-vehicle non-metallic material, which is characterized by: deriving a balance emissionmodel of VOC in the non-metallic material at an environment cabin closed stage and a mass transfer diffusion model of the VOC in the non-metallic material at a direct current emission stage based ona mass transfer emission rule, a mass conservation law and a Henry's law, and measuring key parameters of an emission process of the in-vehicle non-metallic material in combination with actually measured data, wherein the key parameters comprise an initial emittable concentration C0, a distribution coefficient K, and a diffusion coefficient Dm. According to a device and the method for measuring the key parameters of the VOC emission in the in-vehicle non-metallic material, on the basis of a mass transfer diffusion rule and the mass conservation law of the VOC in the non-metallic material underdifferent conditions, the balance emission model of the VOC in the non-metallic material under the condition of closed environment cabin and the mass transfer diffusion model of the VOC in the non-metallic material under the condition of direct current emission are established, in combination with the actually measured data, the key parameters of the emission process of the in-vehicle non-metallic material are measured at the same time, wherein the key parameters comprise the initial emittable concentration C0, the diffusion coefficient Dm and the distribution coefficient K, thereby achieveing the goal of establishing a VOC prediction model of the in-vehicle non-metallic material.