The invention relates to a thermal insulation sleeve for a filter. The thermal insulation sleeve comprises an electric wire, an inner barrel and an outer barrel, wherein the inner barrel and the outer barrel have same cross-sectional shapes, the upper end and the lower end of the inner barrel are open, the upper end and the lower end of the inner barrel are provided with an upper flange and a lower flange respectively, and the upper flange and the lower flange extend outwards; and the upper end of the outer barrel is open, the lower end of the outer barrel is closed, the inner barrel is coaxially sleeved in the outer barrel, and the inner barrel is connected with the outer barrel through the upper flange and the lower flange so that a chamber is formed between the inner barrel and the outer barrel; the electric wire is disposed in the chamber and covered on the outer wall of the inner barrel in a single layer ring-shaped mode, and two ends of the electric wire sequentially penetrate through the lower flange and the lower end of the outer barrel and are located outside the outer barrel. A diesel filter is sleeved in the thermal insulation sleeve, so that the diesel filter is subjected to cold prevention and thermal protection in winter, wax deposition phenomenon of residual diesel oil in the diesel filter is effectively avoided, and a diesel vehicle can be started normally.