An electronic component housing package, comprising: an insulating substrate having a first principal face and a second principal face facing away from each other, the insulating substrate having a lower insulating layer including the second principal face, the lower insulating layer having a mounting section for mounting an electronic component, and a frame-shaped upper insulating layer including the first principal face, the frame-shaped upper insulating layer being provided on the lower insulating layer so as to surround the mounting section; a plurality of external connection conductors provided on the second principal face; and connection conductors provided so as to extend from outer peripheral ends of the external connection conductors to outer peripheral ends of the insulating substrate, respectively, the connection conductors being provided so as to be curved convexly toward a first principal face side over a range from the outer peripheral ends of the external connection conductors to the outer peripheral ends of the insulating substrate in a vertical cross-sectional view of the electronic component housing package and so that a distance from each of the connection conductors to the second principal face is gradually increased in a thickness direction of the insulating substrate, insulating bodies being provided so as to cover the connection conductors, respectively, wherein the insulating bodies each have a third principal face lying in the same plane as the second principal face, and inclined sections are provided from respective ones of the third principal faces to the connection conductors on outer peripheral side surfaces of the insulating bodies on a second principal face side, respectively. an insulating substrate having a first principal face and a second principal face facing away from each other, the insulating substrate having a lower insulating layer including the second principal face, the lower insulating layer having a mounting section for mounting an electronic component, and a frame-shaped upper insulating layer including the first principal face, the frame-shaped upper insulating layer being provided on the lower insulating layer so as to surround the mounting section; a plurality of external connection conductors provided on the second principal face; and connection conductors provided so as to extend from outer peripheral ends of the external connection conductors to outer peripheral ends of the insulating substrate, respectively, the connection conductors being provided so as to be curved convexly toward a first principal face side over a range from the outer peripheral ends of the external connection conductors to the outer peripheral ends of the insulating substrate in a vertical cross-sectional view of the electronic component housing package and so that a distance from each of the connection conductors to the second principal face is gradually increased in a thickness direction of the insulating substrate, insulating bodies being provided so as to cover the connection conductors, respectively, wherein the insulating bodies each have a third principal face lying in the same plane as the second principal face, and inclined sections are provided from respective ones of the third principal faces to the connection conductors on outer peripheral side surfaces of the insulating bodies on a second principal face side, respectively.