an electric circuit including the magnetic detection element 50 can be prevented from becoming moist or being damaged by interference with external parts or the like the positioning section u03b3 positions the current detection device 10 in a vehicle the positioning section u03b3 is not particularly an essential component in the present invention in this embodiment the current detection device is precisely positioned and fixed to a certain part of a vehicle by engaging an engaging edge 33 with a positioning protrusion not shown or the like meanwhile a pair of protrusions 24 a and 24 b extending downwards are provided on a lower face of the sensor body 30 the protrusions 24 a and 24 b are respectively provided on positions corresponding to the connecting section u03b1 and the positioning section u03b3 particularly the through holes 23 a and 23 b of the busbar 20 the protrusions 24 a and 24 b have the size and length so that the protrusions 24 a and 24 b can be inserted in the through holes 23 a and 23 b the size of the protrusions 24 a and 24 b is slightly smaller than that of the through holes 23 a and 23 b and the.