A syringe assembly comprising: a barrel including a cylindrical barrel body that has an opening at a proximal end thereof, and a barrel tip portion that is disposed at a distal end of the barrel body; a puncture needle having an edge surface and a needle hole and being held by the barrel tip portion so as to project from the barrel tip portion; and a cap being detachably mountable to the barrel and sealing a distal end of the needle hole, wherein the cap includes: a receiving hole that receives the puncture needle, a bottom wall portion that is disposed adjacent to a distal end side of the receiving hole and into which the puncture needle is inserted, and a stopper portion that defines an insertion length of the puncture needle relative to the bottom wall portion by abutting against the barrel, and in a state in which the cap is mounted to the barrel, a length from a most proximal position of a contact region between the cap and the puncture needle to a most proximal position of the edge surface is in a range of 1 to 3 mm, and wherein the puncture needle comprises: a first lubricant-covered region formed on an outer surface of the puncture needle; a second lubricant-covered region formed adjacent to an outer surface of a proximal end side of the first lubricant-covered region; and a non-lubricant-covered region formed adjacent to an outer surface of a proximal end side proximal to the second lubricant-covered region, and wherein the first lubricant-covered region extends from a most distal position of the puncture needle to a position in a range of 1 to 3 mm from the most proximal position of the edge surface and has a smaller lubricant-covering thickness than the second lubricant-covered region, and the bottom wall portion of the cap has a Shore D hardness in range of 35 to 55. a barrel including a cylindrical barrel body that has an opening at a proximal end thereof, and a barrel tip portion that is disposed at a distal end of the barrel body; a puncture needle having an edge surface and a needle hole and being held by the barrel tip portion so as to project from the barrel tip portion; and a cap being detachably mountable to the barrel and sealing a distal end of the needle hole, wherein the cap includes: a receiving hole that receives the puncture needle, a bottom wall portion that is disposed adjacent to a distal end side of the receiving hole and into which the puncture needle is inserted, and a stopper portion that defines an insertion length of the puncture needle relative to the bottom wall portion by abutting against the barrel, and in a state in which the cap is mounted to the barrel, a length from a most proximal position of a contact region between the cap and the puncture needle to a most proximal position of the edge surface is in a range of 1 to 3 mm, and wherein the puncture needle comprises: a receiving hole that receives the puncture needle, a bottom wall portion that is disposed adjacent to a distal end side of the receiving hole and into which the puncture needle is inserted, and a stopper portion that defines an insertion length of the puncture needle relative to the bottom wall portion by abutting against the barrel, and in a state in which the cap is mounted to the barrel, a length from a most proximal position of a contact region between the cap and the puncture needle to a most proximal position of the edge surface is in a range of 1 to 3 mm, and wherein the puncture needle comprises: a first lubricant-covered region formed on an outer surface of the puncture needle; a second lubricant-covered region formed adjacent to an outer surface of a proximal end side of the first lubricant-covered region; and a non-lubricant-covered region formed adjacent to an outer surface of a proximal end side proximal to the second lubricant-covered region, and wherein the first lubricant-covered region extends from a most distal position of the puncture needle to a position in a range of 1 to 3 mm from the most proximal position of the edge surface and has a smaller lubricant-covering thickness than the second lubricant-covered region, and the bottom wall portion of the cap has a Shore D hardness in range of 35 to 55.