PROBLEM TO BE SOLVED: To provide a detection device capable of achieving both of good adhesion between an impurity semiconductor layer and a pixel electrode and good dark current characteristics of a conversion element, and securing good transfer speed.SOLUTION: In a detection device having a conversion element 12 which has a pixel electrode, an impurity semiconductor layer 123 and a semiconductor layer 124 in order from a substrate 100 side and converts radioactive ray or light into electrical charge, the pixel electrode contains a metal layer 122 having a gap 122 formed in a region overlapping an orthogonal projection of the semiconductor layer 124.