A pillar member of a vehicle, comprising: a pillar body portion having at least one closed cross-sectional portion; and a connection bonding portion (200,210,230) disposed on opposing side surfaces of the pillar body portion and consecutively cast to be connected to the pillar body portion, in order to be combined with a vehicle frame, wherein the connection bonding portion (210, 230) includes a first connection bonding portion disposed on one side of the pillar body portion and a second connection bonding portion disposed on the other side of the pillar body portion to oppose the first connection bonding portion, and the pillar body portion is consecutively cast using a roll forming method in a section between the first connection bonding portion and the second connection bonding portion, thereby forming an even number of closed cross-sectional portions, wherein at least the pillar body portion between the pillar body portion and the connection bonding portion (210, 230) is configured using a material selected from among martensitic steel, complex phase steel, dual phase steel, transformation induced plasticity (TRIP) steel, and twinning induced plasticity (TWIP) steel, having strength of 980 MPa or higher, and wherein each respective connection bonding portion (210, 230) is disposed on a portion of an opposing side surface of the pillar body portion in a length direction, the pillar member being characterized in that each closed cross-sectional portion and the associated said bonding portion are bonded by welding; and in that each respective connection bonding portion (210,230) is not formed on an entirety of the associated said opposing side surface of the pillar body portion in the length direction. a pillar body portion having at least one closed cross-sectional portion; and a connection bonding portion (200,210,230) disposed on opposing side surfaces of the pillar body portion and consecutively cast to be connected to the pillar body portion, in order to be combined with a vehicle frame, wherein the connection bonding portion (210, 230) includes a first connection bonding portion disposed on one side of the pillar body portion and a second connection bonding portion disposed on the other side of the pillar body portion to oppose the first connection bonding portion, and the pillar body portion is consecutively cast using a roll forming method in a section between the first connection bonding portion and the second connection bonding portion, thereby forming an even number of closed cross-sectional portions, wherein at least the pillar body portion between the pillar body portion and the connection bonding portion (210, 230) is configured using a material selected from among martensitic steel, complex phase steel, dual phase steel, transformation induced plasticity (TRIP) steel, and twinning induced plasticity (TWIP) steel, having strength of 980 MPa or higher, and wherein each respective connection bonding portion (210, 230) is disposed on a portion of an opposing side surface of the pillar body portion in a length direction, the pillar member being characterized in that each closed cross-sectional portion and the associated said bonding portion are bonded by welding; and in that each respective connection bonding portion (210,230) is not formed on an entirety of the associated said opposing side surface of the pillar body portion in the length direction.