A spark plug comprising: a center electrode; an insulator having an axial hole extending in an axial direction and holding the center electrode in the axial hole; a metal shell which holds the insulator and surrounds a radial periphery of the insulator in a circumferential direction; a ground electrode (30, 230, 330, 430, 530, 630, 730, 830) comprising a first end portion joined to the metal shell and a second end portion, the ground electrode (30, 230, 330, 430, 530, 630, 730, 830) being bent such that the second end portion faces a leading end portion of the center electrode; and an electrode chip (70, 270, 370, 470, 570, 670, 770, 870) joined to the ground electrode (30, 230, 330, 430, 530, 630, 730, 830) in a state in which the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) is engaged in a recess portion (35, 235, 335, 435, 535, 635, 735, 835) formed in the second end portion of the ground electrode (30, 230, 330, 430, 530, 630, 730, 830) at a position opposing the leading end portion of the center electrode, wherein the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) is formed by previously welding a chip body portion (71, 271, 371, 471, 571, 671, 771, 871) formed of noble metal or an alloy containing a noble metal as a main component and a chip holding portion (76, 276, 376, 476, 576, 676, 776, 876) formed of Ni or an alloy containing Ni as a main component prior to joining the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) to the ground electrode (30, 230, 330, 430, 530, 630, 730, 830), wherein a first molten bond (81, 281, 381, 481, 581, 681, 781, 881) is formed by welding the chip body portion (71, 271, 371, 471, 571, 671, 771, 871) and the chip holding portion (76276, 376, 476, 576, 676, 776, 876), characterized in that the first molten bond (81, 281, 381, 481, 581, 681, 781, 881) is placed in the recess portion (35, 235, 335, 435, 535, 635, 735, 835) so as not to be exposed to an outside environment, in a state in which the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) is engaged in the recess portion (35, 235, 335, 435, 535, 635, 735, 835) and joined to the ground electrode (30, 230, 330, 430, 530, 630, 730, 830). a center electrode; an insulator having an axial hole extending in an axial direction and holding the center electrode in the axial hole; a metal shell which holds the insulator and surrounds a radial periphery of the insulator in a circumferential direction; a ground electrode (30, 230, 330, 430, 530, 630, 730, 830) comprising a first end portion joined to the metal shell and a second end portion, the ground electrode (30, 230, 330, 430, 530, 630, 730, 830) being bent such that the second end portion faces a leading end portion of the center electrode; and an electrode chip (70, 270, 370, 470, 570, 670, 770, 870) joined to the ground electrode (30, 230, 330, 430, 530, 630, 730, 830) in a state in which the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) is engaged in a recess portion (35, 235, 335, 435, 535, 635, 735, 835) formed in the second end portion of the ground electrode (30, 230, 330, 430, 530, 630, 730, 830) at a position opposing the leading end portion of the center electrode, wherein the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) is formed by previously welding a chip body portion (71, 271, 371, 471, 571, 671, 771, 871) formed of noble metal or an alloy containing a noble metal as a main component and a chip holding portion (76, 276, 376, 476, 576, 676, 776, 876) formed of Ni or an alloy containing Ni as a main component prior to joining the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) to the ground electrode (30, 230, 330, 430, 530, 630, 730, 830), wherein a first molten bond (81, 281, 381, 481, 581, 681, 781, 881) is formed by welding the chip body portion (71, 271, 371, 471, 571, 671, 771, 871) and the chip holding portion (76276, 376, 476, 576, 676, 776, 876), characterized in that the first molten bond (81, 281, 381, 481, 581, 681, 781, 881) is placed in the recess portion (35, 235, 335, 435, 535, 635, 735, 835) so as not to be exposed to an outside environment, in a state in which the electrode chip (70, 270, 370, 470, 570, 670, 770, 870) is engaged in the recess portion (35, 235, 335, 435, 535, 635, 735, 835) and joined to the ground electrode (30, 230, 330, 430, 530, 630, 730, 830).