A current resonant type DC voltage converter includes: a switching circuit configured to generate an AC voltage from a DC input voltage; a LC resonance circuit configured to resonate in response to application of the AC voltage to a resonant capacitor and a resonant coil; a transformer having a primary side connected in series to the LC resonance circuit; a parallel resonant inductance present in parallel to the transformer; a rectifier circuit configured to rectify a current appearing on a secondary side of the transformer to generate a DC output voltage; and a parallel resonant inductance adjustment circuit configured to change the parallel resonant inductance.