A suspension coil spring comprising: a lower end turn portion which is less than one turn from a lower end of a wire formed into a helical shape; and an upper end turn portion which is less than one turn from an upper end of the wire, at least the lower end turn portion comprising a first portion (12a 1) which ranges from the lower end of the wire to a point exceeding 0.5 turns and configured to be always in contact with a lower spring seat (13, 103) irrespective of magnitude of a load, a second portion (12a 2) which is contiguous with the first portion (12a 1) and extends to a point that is less than one turn from the lower end of the wire and configured to contact the lower spring seat (13, 103) or to be separated from the lower spring seat (13, 103) in accordance with the magnitude of the load, and a third portion (12a 3) configured to be always separated from the lower spring seat (13, 103) irrespective of the magnitude of the load, the suspension coil spring comprising: a compressive residual stress portion between the lower end turn portion and the upper end turn portion, a compressive residual stress from a surface of the wire to a first depth being imparted to the compressive residual stress portion; characterized in that the suspension coil spring further comprises: a deep residual stress portion in a region including the second portion (12a 2) of the lower end turn portion, a compressive residual stress from a surface of the wire to a second depth deeper than the first depth being imparted to the deep residual stress portion. a lower end turn portion which is less than one turn from a lower end of a wire formed into a helical shape; and an upper end turn portion which is less than one turn from an upper end of the wire, at least the lower end turn portion comprising a first portion (12a 1) which ranges from the lower end of the wire to a point exceeding 0.5 turns and configured to be always in contact with a lower spring seat (13, 103) irrespective of magnitude of a load, a second portion (12a 2) which is contiguous with the first portion (12a 1) and extends to a point that is less than one turn from the lower end of the wire and configured to contact the lower spring seat (13, 103) or to be separated from the lower spring seat (13, 103) in accordance with the magnitude of the load, and a third portion (12a 3) configured to be always separated from the lower spring seat (13, 103) irrespective of the magnitude of the load, the suspension coil spring comprising: a compressive residual stress portion between the lower end turn portion and the upper end turn portion, a compressive residual stress from a surface of the wire to a first depth being imparted to the compressive residual stress portion; characterized in that the suspension coil spring further comprises: a deep residual stress portion in a region including the second portion (12a 2) of the lower end turn portion, a compressive residual stress from a surface of the wire to a second depth deeper than the first depth being imparted to the deep residual stress portion. a compressive residual stress portion between the lower end turn portion and the upper end turn portion, a compressive residual stress from a surface of the wire to a first depth being imparted to the compressive residual stress portion; characterized in that the suspension coil spring further comprises: a deep residual stress portion in a region including the second portion (12a 2) of the lower end turn portion, a compressive residual stress from a surface of the wire to a second depth deeper than the first depth being imparted to the deep residual stress portion.