A magnetic carrier, comprising: a resin-filled magnetic core particle, which is constituted by a porous magnetic particle and a resin disposed in pores of the porous magnetic particle; and a resin covering layer provided on a surface of the resin-filled magnetic core particle, wherein a resin for use in the resin covering layer is a copolymer of: a vinyl monomer having a cyclic hydrocarbon group in its molecular structure, and another vinyl monomer, the magnetic carrier has a specific resistance at an electric field strength of 2000 V/cm, measured as described in the description, of 1.0 x 10 7 Ω · cm or more and 1.0 x 10 10 Ω · cm or less, the magnetic carrier has a 50% particle diameter of 30.0 μm or more and 80.0 μm or less on a volume basis, an electric current flowing through the magnetic carrier at a voltage of 500 V, measured as described in the description, ranges from 8.0 to 50.0 μA, and a proportion JR1 of a composition that is made up of the resin in a magnetic carrier portion of a region R1, measured as described in the description, and a proportion JR2 of the composition in a magnetic carrier portion of a region R2, measured as described in the description, satisfy the following relationship, the region R1 and the region R2 being defined as described below. 1.20 ≤ JR 2 / JR 1 ≤ 2.00 Definition of region R1: A line segment having a maximum length is drawn on a cross section image of the magnetic carrier. Two straight lines A and B that are parallel to the line segment and are separated from the line segment by 2.5 μm are drawn. A straight line C that passes through a point of contact between the line segment and a surface of the resin-filled magnetic core particle and is perpendicular to the line segment is drawn. A straight line D that is parallel to the straight line C, is closer to the center of the magnetic carrier than the straight line C, and is separated from the straight line C by 5.0 μm is drawn. The region R1 refers to a region surrounded by the straight lines A, B, and D and a circumference of the resin-filled magnetic core particle. Definition of region R2: A straight line E that is parallel to the straight line D, is closer to the center of the magnetic carrier than the straight line D, and is separated from the straight line D by 5.0 μm is drawn. The region R2 refers to a region surrounded by the straight lines A, B, D, and E. a resin-filled magnetic core particle, which is constituted by a porous magnetic particle and a resin disposed in pores of the porous magnetic particle; and a resin covering layer provided on a surface of the resin-filled magnetic core particle, wherein a resin for use in the resin covering layer is a copolymer of: a vinyl monomer having a cyclic hydrocarbon group in its molecular structure, and another vinyl monomer, a vinyl monomer having a cyclic hydrocarbon group in its molecular structure, and another vinyl monomer, the magnetic carrier has a specific resistance at an electric field strength of 2000 V/cm, measured as described in the description, of 1.0 x 10 7 Ω · cm or more and 1.0 x 10 10 Ω · cm or less, the magnetic carrier has a 50% particle diameter of 30.0 μm or more and 80.0 μm or less on a volume basis, an electric current flowing through the magnetic carrier at a voltage of 500 V, measured as described in the description, ranges from 8.0 to 50.0 μA, and a proportion JR1 of a composition that is made up of the resin in a magnetic carrier portion of a region R1, measured as described in the description, and a proportion JR2 of the composition in a magnetic carrier portion of a region R2, measured as described in the description, satisfy the following relationship, the region R1 and the region R2 being defined as described below. 1.20 ≤ JR 2 / JR 1 ≤ 2.00 Definition of region R1: A line segment having a maximum length is drawn on a cross section image of the magnetic carrier. Two straight lines A and B that are parallel to the line segment and are separated from the line segment by 2.5 μm are drawn. A straight line C that passes through a point of contact between the line segment and a surface of the resin-filled magnetic core particle and is perpendicular to the line segment is drawn. A straight line D that is parallel to the straight line C, is closer to the center of the magnetic carrier than the straight line C, and is separated from the straight line C by 5.0 μm is drawn. The region R1 refers to a region surrounded by the straight lines A, B, and D and a circumference of the resin-filled magnetic core particle. Definition of region R2: A line segment having a maximum length is drawn on a cross section image of the magnetic carrier. Two straight lines A and B that are parallel to the line segment and are separated from the line segment by 2.5 μm are drawn. A straight line C that passes through a point of contact between the line segment and a surface of the resin-filled magnetic core particle and is perpendicular to the line segment is drawn. A straight line D that is parallel to the straight line C, is closer to the center of the magnetic carrier than the straight line C, and is separated from the straight line C by 5.0 μm is drawn. The region R1 refers to a region surrounded by the straight lines A, B, and D and a circumference of the resin-filled magnetic core particle. Definition of region R2: A straight line E that is parallel to the straight line D, is closer to the center of the magnetic carrier than the straight line D, and is separated from the straight line D by 5.0 μm is drawn. The region R2 refers to a region surrounded by the straight lines A, B, D, and E.