A discharge ionization current detector of the present invention is used for a detector for a gas chromatograph and suitable for analyzing high-boiling components. A discharge ionization current detector 10 is mainly constituted by a plasma generating section 20 and an ion collecting section 30. Regarding the ion collecting section 30, an ion collecting electrode 31 and a bias electrode 32 are arranged, and furthermore, an insulating member made of sapphire or aluminum oxide having a purity equal to or greater than 99.5% is arranged between the ion collecting electrode 31 and the bias electrode 32.