To provide a banking angle detector of a vehicle which can precisely remove a sensor drift amount, and can enhance the estimated precision of a banking angle.

There are included: an angular velocity sensor 55 for detecting a roll rate and a yaw rate of a vehicle; a roll rate estimating circuit 60 for calculating an estimated roll rate P which is angular velocity around front and rear axes based on the roll rate, the yaw rate, and a travelling speed v; a bank angle estimating means 59 for calculating an estimated bank angle δ from the estimated roll rate P; a forward movement determining means 67 for determining a forward movement state based on the estimated roll rate P and an estimated yaw rate R in travelling; a drift amount estimating means in forward movement 69 for estimating a drift amount in forward movement D1 from an output ω of the angular velocity sensor 55 when the forward movement determining means 67 determines as the forward movement; and an angular velocity correcting means 71 for correcting the output ω of the angular velocity sensor 55 by the drift amount in forward movement D1.