A method for producing a high-purity aqueous urea solution in a urea production process, the process comprising the steps of: (a) synthesizing urea from a raw material feed to produce a urea synthesis liquid, (b) purifying the urea synthesis liquid to produce an aqueous urea solution having high urea concentration by separating ammonia and carbon dioxide from the urea synthesis liquid, (b1) recovering the separated ammonia and carbon dioxide in step (b); (c) separating a part of the aqueous urea solution having high urea concentration after step (b), (c1) crystallizing the part of the aqueous urea solution having high urea concentration separated in step (c) to produce a slurry containing crystal urea being a solid and a mother liquid; (c2) separating the slurry produced in the step (c1) to separate the crystal urea and the mother liquid; (c3) selectively and optionally sending back a part of the mother liquid separated in step (c2) to step (a) via step (b1), wherein the mother liquid is sent back to step (a) with recovered liquid from step (bl); (c4) mixing the crystal urea separated in step (c2) with water to produce a high-purity aqueous urea solution, (d) concentrating the rest of the aqueous urea solution separated in step (c), and (e) producing solid granular urea from the concentrated aqueous urea solution produced in step (d). (a) synthesizing urea from a raw material feed to produce a urea synthesis liquid, (b) purifying the urea synthesis liquid to produce an aqueous urea solution having high urea concentration by separating ammonia and carbon dioxide from the urea synthesis liquid, (b1) recovering the separated ammonia and carbon dioxide in step (b); (c) separating a part of the aqueous urea solution having high urea concentration after step (b), (c1) crystallizing the part of the aqueous urea solution having high urea concentration separated in step (c) to produce a slurry containing crystal urea being a solid and a mother liquid; (c2) separating the slurry produced in the step (c1) to separate the crystal urea and the mother liquid; (c3) selectively and optionally sending back a part of the mother liquid separated in step (c2) to step (a) via step (b1), wherein the mother liquid is sent back to step (a) with recovered liquid from step (bl); (c4) mixing the crystal urea separated in step (c2) with water to produce a high-purity aqueous urea solution, (c1) crystallizing the part of the aqueous urea solution having high urea concentration separated in step (c) to produce a slurry containing crystal urea being a solid and a mother liquid; (c2) separating the slurry produced in the step (c1) to separate the crystal urea and the mother liquid; (c3) selectively and optionally sending back a part of the mother liquid separated in step (c2) to step (a) via step (b1), wherein the mother liquid is sent back to step (a) with recovered liquid from step (bl); (c4) mixing the crystal urea separated in step (c2) with water to produce a high-purity aqueous urea solution, (d) concentrating the rest of the aqueous urea solution separated in step (c), and (e) producing solid granular urea from the concentrated aqueous urea solution produced in step (d). <EOS>