A Hall sensor having a ball portion on a magnetosensitive portion is provided. A Hall sensor is provided, including: a substrate; a magnetosensitive portion formed on the substrate; an insulating film formed on the magnetosensitive portion; an electrode portion formed on the insulating film; and a ball portion which is provided on the electrode portion and is electrically connected to the electrode portion, wherein in plan view, a projection area of the ball portion accounts for 10% or more of a projection area of the magnetosensitive portion. The projection area of the ball portion may account for 20% or more of the projection area of the magnetosensitive portion. A bonding wire which is electrically connected to the ball portion and is extended from the ball portion in a direction perpendicular to an upper surface of the electrode portion may be further included.