A ceramic porous body comprising: skeleton portions; and pore portions formed between the skeleton portions, the pore portions being capable of allowing a fluid to flow therethrough. In the ceramic porous body, the pore portions satisfy the following equations (1) and (2) in a cross section parallel to a flow direction of the fluid; L1/L2≥0.92  (1), and L1+L2≤27 μm  (2) in which L1 is an average length of the pore portions in the flow direction of the fluid; and L2 is an average length of the pore portions in a direction orthogonal to the flow direction of the fluid.