A polymer polyol composition comprising a dispersion medium composed of a polyol, or and a diluent, and polymer particles dispersed in the dispersion medium, wherein the polyol is a compound formed by adding an alkylene oxide to a compound containing two or more active hydrogen atoms, wherein the polymer particles are formed by polymerizing an ethylenically unsaturated compound (b) in the dispersion medium in the presence of a dispersant, and wherein at least 5 mass% of (b) comprises a terminal ethylenically-unsaturated group containing compound that has a number-average molecular weight of 160 to 490 and a solubility parameter SP of 9.5 to 12.5, and that is at least one compound selected from compounds to:: (poly)oxy-C 2 -C 8 -alkylene ether of a terminal unsaturated C 3 -C 24 -alcohol;: compound expressed by a general formula shown below;: compound expressed by a general formula shown below;: compound expressed by a general formula shown below; and: compound expressed by a general formula shown below: CH 2 = CRCOO k COCH 2 COCH 3 CH 2 = CRCOO k [CO(CH 2) s O] m n H CH 2 = CRCO[O(CH 2) s CO] n O n H CH 2 = CRCOO k [QO p] r t H wherein: R represents a hydrogen atom or a methyl group; A represents an alkylene group having 2 to 8 carbon atoms; Q represents a residue obtained by removing two OH groups from a dicarboxylic acid; k represents an integer of not less than 1 that provides a number average molecular weight of not more than 490; n and p represent 0 or integers of not less than 1 that provide a number-average molecular weight of not more than 490; s represents an integer of 3 to 7; m and r are integers of not less than 1 that provide a number-average molecular weight of not more than 490; and t represents 0 or 1, wherein the solubility parameter SP refers to the parameter expressed by the square root of the ratio of the cohesive energy density ΔE to the molar volume V as follows: Solubility Parameter = ΔE / V 1 / 2.: (poly)oxy-C 2 -C 8 -alkylene ether of a terminal unsaturated C 3 -C 24 -alcohol;: compound expressed by a general formula shown below;: compound expressed by a general formula shown below;: compound expressed by a general formula shown below; and: compound expressed by a general formula shown below: CH 2 = CRCOO k COCH 2 COCH 3 CH 2 = CRCOO k [CO(CH 2) s O] m n H CH 2 = CRCO[O(CH 2) s CO] n O n H CH 2 = CRCOO k [QO p] r t H wherein: R represents a hydrogen atom or a methyl group; A represents an alkylene group having 2 to 8 carbon atoms; Q represents a residue obtained by removing two OH groups from a dicarboxylic acid; k represents an integer of not less than 1 that provides a number average molecular weight of not more than 490; n and p represent 0 or integers of not less than 1 that provide a number-average molecular weight of not more than 490; s represents an integer of 3 to 7; m and r are integers of not less than 1 that provide a number-average molecular weight of not more than 490; and t represents 0 or 1, wherein the solubility parameter SP refers to the parameter expressed by the square root of the ratio of the cohesive energy density ΔE to the molar volume V as follows: Solubility Parameter = ΔE / V 1 / 2. R represents a hydrogen atom or a methyl group; A represents an alkylene group having 2 to 8 carbon atoms; Q represents a residue obtained by removing two OH groups from a dicarboxylic acid; k represents an integer of not less than 1 that provides a number average molecular weight of not more than 490; n and p represent 0 or integers of not less than 1 that provide a number-average molecular weight of not more than 490; s represents an integer of 3 to 7; m and r are integers of not less than 1 that provide a number-average molecular weight of not more than 490; and t represents 0 or 1, wherein the solubility parameter SP refers to the parameter expressed by the square root of the ratio of the cohesive energy density ΔE to the molar volume V as follows: Solubility Parameter = ΔE / V 1 / 2.