A variable turbocharger including a turbine housing, a first scroll fluidly communicating with a turbine, a second scroll formed along an outside of the first scroll, wherein the first scroll and the second scroll are disposed within the turbine housing for exhaust gas to exhaust through the turbine, a partitioning unit for selectively separating the first scroll and the second scroll, and a a flux control valve disposed at the exhaust gas inflow portion and selectively coupled to the partitioning unit for blocking the exhaust gas from flowing into the second scroll. The variable turbocharger may prevent turbo lag at a low speed and be highly efficient at a high speed.