An antifouling structure, comprising: a non-volatile liquid consisting of a fluorinated oil or a silicone oil; a microporous structure layer retaining the non-volatile liquid, wherein the microporous structure layer comprises a silicon oxide-based inorganic material, wherein the surface and the pores of the microporous structure layer are modified with a modifier that contains a compound having a fluoride functional group that is bound to the inorganic material of the microporous structure layer; and a base with the microporous structure layer on a surface, wherein a surface roughness (Rz) of the microporous structure layer and the a film thickness of the non-volatile liquid satisfy Rz < T, wherein the film thickness of the non-volatile liquid is equal to or less than 300 nm, wherein the surface roughness (Rz) is measured in the following conditions: device name: NANOSCOPE IIIa + D3100, Probe: OMCL-AC160TS, measuring condition: tapping mode AFM, 3x3 μm area, wherein the film thickness is measured in the following conditions: measuring device: VASE, which is a Variable Angle Spectroscopic Ellipsometer, measuring condition: wavelength: 300 nm to 1800 nm, and wherein the surface roughness (Rz) of the microporous structure layer is equal to or less than 100 nm. a non-volatile liquid consisting of a fluorinated oil or a silicone oil; a microporous structure layer retaining the non-volatile liquid, wherein the microporous structure layer comprises a silicon oxide-based inorganic material, wherein the surface and the pores of the microporous structure layer are modified with a modifier that contains a compound having a fluoride functional group that is bound to the inorganic material of the microporous structure layer; and a base with the microporous structure layer on a surface, wherein a surface roughness (Rz) of the microporous structure layer and the a film thickness of the non-volatile liquid satisfy Rz < T, wherein the film thickness of the non-volatile liquid is equal to or less than 300 nm, wherein the surface roughness (Rz) is measured in the following conditions: device name: NANOSCOPE IIIa + D3100, Probe: OMCL-AC160TS, measuring condition: tapping mode AFM, 3x3 μm area, wherein the film thickness is measured in the following conditions: measuring device: VASE, which is a Variable Angle Spectroscopic Ellipsometer, measuring condition: wavelength: 300 nm to 1800 nm, and wherein the surface roughness (Rz) of the microporous structure layer is equal to or less than 100 nm. wherein a surface roughness (Rz) of the microporous structure layer and the a film thickness of the non-volatile liquid satisfy Rz < T, wherein the film thickness of the non-volatile liquid is equal to or less than 300 nm, wherein the surface roughness (Rz) is measured in the following conditions: device name: NANOSCOPE IIIa + D3100, Probe: OMCL-AC160TS, measuring condition: tapping mode AFM, 3x3 μm area, wherein the film thickness is measured in the following conditions: measuring device: VASE, which is a Variable Angle Spectroscopic Ellipsometer, measuring condition: wavelength: 300 nm to 1800 nm, and wherein the surface roughness (Rz) of the microporous structure layer is equal to or less than 100 nm.