A connector for connecting a first circuit board (11, 51, 61) having two or more first contact portions (14, 64) that are bendable and a second circuit board (21, 52, 71) having two or more second contact portions (24, 74) that are bendable, the connector comprising: a first connector portion (31, 53, 81, 101) in which two or more projection units (34, 84, 104) project from a surface of a base plate; and a second connector portion (41, 54, 91) constituted of a fitting plate in which two or more fitting hole units (44, 94) corresponding to the two or more projection units are formed, wherein at least one of the two or more projection units and the two or more fitting hole units have elasticity, and wherein when the first connector portion and the second connector portion are fitted with each other, each of the two or more projection units (34, 84, 104) of the first connector portion is fitted into a corresponding one of the two or more fitting hole units (44, 94) of the second connector portion as catching each of the two or more first contact portions (14, 64) of the first circuit board and a corresponding one of the two or more second contact portions (24, 74) of the second circuit board that are overlapped to face each other, and the each of the two or more first contact portions of the first circuit board and the corresponding one of the two or more second contact portions of the second circuit board are configured to be elastically pressed into contact with each other and thus electrically connected to each other between a lateral surface of the each of the two or more projection units and an inner surface of the corresponding one of the two or more fitting hole units, characterized in that: the first connector portion (31, 53, 81, 101) has at least one locking portion that is elastically deformable and is situated between, of the two or more projection units, at least one pair of adjacent projection units (34, 84, 104), wherein the second connector portion (41, 54, 91) has at least one portion to be locked corresponding to the at least one locking portion of the first connector portion, wherein when the first connector portion and the second connector portion are fitted with each other each of the at least one locking portion is caught on a corresponding portion to be locked whereby a fitting state between the first connector portion and the second connector portion is locked. a first connector portion (31, 53, 81, 101) in which two or more projection units (34, 84, 104) project from a surface of a base plate; and a second connector portion (41, 54, 91) constituted of a fitting plate in which two or more fitting hole units (44, 94) corresponding to the two or more projection units are formed, wherein at least one of the two or more projection units and the two or more fitting hole units have elasticity, and wherein when the first connector portion and the second connector portion are fitted with each other, each of the two or more projection units (34, 84, 104) of the first connector portion is fitted into a corresponding one of the two or more fitting hole units (44, 94) of the second connector portion as catching each of the two or more first contact portions (14, 64) of the first circuit board and a corresponding one of the two or more second contact portions (24, 74) of the second circuit board that are overlapped to face each other, and the each of the two or more first contact portions of the first circuit board and the corresponding one of the two or more second contact portions of the second circuit board are configured to be elastically pressed into contact with each other and thus electrically connected to each other between a lateral surface of the each of the two or more projection units and an inner surface of the corresponding one of the two or more fitting hole units, the first connector portion (31, 53, 81, 101) has at least one locking portion that is elastically deformable and is situated between, of the two or more projection units, at least one pair of adjacent projection units (34, 84, 104), wherein the second connector portion (41, 54, 91) has at least one portion to be locked corresponding to the at least one locking portion of the first connector portion, wherein when the first connector portion and the second connector portion are fitted with each other each of the at least one locking portion is caught on a corresponding portion to be locked whereby a fitting state between the first connector portion and the second connector portion is locked.