To provide a method for manufacturing a silicon nitride filter being highly air-permeable, excellent in the catching and removing efficiency of particulates and suitable as a DPF.

The silicon nitride filter where metal silicon is substantially converted to silicon nitride is manufactured by heat-treating a formed body containing metal silicon particles and a pore forming material in nitrogen. In the whole mass of the pore forming material, the content of approximately spherical particles having an average particle diameter of 10-30 μm is 10-50 mass% and approximately spherical particles having an average particle diameter of 40-100 μm is 90-50 mass%.

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