Polymer polyol and method for producing polyurethane

A polymer polyol (A) in which polymer fine particles (JR) having an ethylenically unsaturated compound (E) as a constituent unit are contained in a polyol (PL), wherein the (PL) comprises the following polyol (a), and the volume average particle diameter (R) of the (JR) is from 0.1 to 1.5 μm;

• polyol (a):
• a polyether polyol resulting from random and/or block addition of an alkylene oxide mainly composed of a 1,2-alkylene oxide to an active hydrogen-containing compound, wherein the average number x of moles of ethylene oxide added per active hydrogen atom is 20 or less, the primary hydroxidation ratio y of terminal hydroxyl groups is 40% or more, and x and y (%) satisfy a relationship of the following formula (1) when x is from 10 to 20 and a relationship of the following formula (2) when x is less than 10;
• y≧0.328x+90.44 (1)
• y≧42x0.47(1−x/41) (2).