Urethane resin particles which are either of urethane resin particles or urethane resin particles: the urethane resin particles comprising a urethane or urethane-urea resin having a structural unit (x) represented by general formula: wherein the urethane or urethane-urea resin is a polyurethane resin obtained by reacting an active hydrogen component with an isocyanate component, the active hydrogen component containing an active hydrogen-containing compound represented by general formula: wherein in the general formula and the general formula, R 1 is represented by general formula: -O-CH 2 -R 5 wherein R 5 represents a monovalent hydrocarbon group having a carbon number of 1 to 28; R 2 is a residue derived from a divalent active hydrogen-containing compound by removing two active hydrogens, and a plurality of R 2 may be the same or different from each other; Y is a residue derived from a trivalent aromatic polycarboxylic acid by removing all carboxyl groups; and a and b are each an integer of 1 or 2, wherein a + b = 3, that has residues (j) bonded thereto covalently, the residues (j) being residues derived from a trivalent aromatic polycarboxylic acid by removing hydroxyl groups; or the urethane resin particles comprising a urethane resin composition which comprises both a urethane or urethane-urea resin and a compound that has a residue (j) derived from a tri- or more valent aromatic polycarboxylic acid by removing hydroxyl groups, the compound being represented by the general formula; wherein the residues (j) derived from a tri- or more valent aromatic polycarboxylic acid by removing hydroxyl groups are linked respectively to urethane or urea groups (u) of the or by hydrogen bonds: wherein in the general formula, R 3 represents a residue derived from a monovalent active hydrogen-containing compound by removing one active hydrogen, and a plurality of R 3 may be the same or different from each other; V represents a residue derived from a tri- or more valent aromatic polycarboxylic acid by removing all carboxyl groups, and in the aromatic ring of V, a hydrogen atom is bonded to at least one ring carbon; c is an integer satisfying 2 ≤ c ≤ (the number of substituents capable of being directly linked to the aromatic ring - 2); W represents a residue derived from an m- or more valent active hydrogen-containing compound by removing m active hydrogens; and m is an integer of 2 to 10. the urethane resin particles comprising a urethane or urethane-urea resin having a structural unit (x) represented by general formula: wherein the urethane or urethane-urea resin is a polyurethane resin obtained by reacting an active hydrogen component with an isocyanate component, the active hydrogen component containing an active hydrogen-containing compound represented by general formula: wherein in the general formula and the general formula, R 1 is represented by general formula: -O-CH 2 -R 5 wherein R 5 represents a monovalent hydrocarbon group having a carbon number of 1 to 28; R 2 is a residue derived from a divalent active hydrogen-containing compound by removing two active hydrogens, and a plurality of R 2 may be the same or different from each other; Y is a residue derived from a trivalent aromatic polycarboxylic acid by removing all carboxyl groups; and a and b are each an integer of 1 or 2, wherein a + b = 3, that has residues (j) bonded thereto covalently, the residues (j) being residues derived from a trivalent aromatic polycarboxylic acid by removing hydroxyl groups; or the urethane resin particles comprising a urethane resin composition which comprises both a urethane or urethane-urea resin and a compound that has a residue (j) derived from a tri- or more valent aromatic polycarboxylic acid by removing hydroxyl groups, the compound being represented by the general formula; wherein the residues (j) derived from a tri- or more valent aromatic polycarboxylic acid by removing hydroxyl groups are linked respectively to urethane or urea groups (u) of the or by hydrogen bonds: wherein in the general formula, R 3 represents a residue derived from a monovalent active hydrogen-containing compound by removing one active hydrogen, and a plurality of R 3 may be the same or different from each other; V represents a residue derived from a tri- or more valent aromatic polycarboxylic acid by removing all carboxyl groups, and in the aromatic ring of V, a hydrogen atom is bonded to at least one ring carbon; c is an integer satisfying 2 ≤ c ≤ (the number of substituents capable of being directly linked to the aromatic ring - 2); W represents a residue derived from an m- or more valent active hydrogen-containing compound by removing m active hydrogens; and m is an integer of 2 to 10.