NOVELTY - A titanium or titanium alloy material consists of a titanium oxide film formed on the outermost surface, and has titanium hydride content rate of more than 55%, which is calculated using a specific relation (I). The content of carbon, nitrogen, and boron in position at which the surface of titanium or titanium alloy material is sputtered by argon is less than 10 atomic%, less than 1 atomic%, and less than 1 atomic%, respectively. The increase amount of contact resistance in the titanium or titanium alloy material before and after a deterioration test is less than 10 m( Omega )cm2.    USE - Titanium or titanium alloy material is used for forming fuel cell separator of polymer electrolyte fuel cell (all claimed) used for motor vehicle and electric power generation system.    ADVANTAGE - The titanium or titanium alloy material provides fuel cell separator with excellent contact electroconductivity and durability.    DETAILED DESCRIPTION - A titanium or titanium alloy material consists of a titanium oxide film formed on the outermost surface, and has titanium hydride content rate of more than 55%, which is calculated using the relation: ((ITiH/ITi+ITiH)x 100) (I), where ITi and ITiH are the maximum intensity of metal titanium and the maximum intensity of titanium hydride at X-ray diffraction peak measured at an incidence angle to the surface of 0.3 degrees . The content of carbon, nitrogen, and boron in position at which the surface of titanium or titanium alloy material is sputtered by argon of 5 nm is less than 10 atomic%, less than 1 atomic%, and less than 1 atomic%, respectively. The increase amount of contact resistance in the titanium or titanium alloy material before and after a deterioration test is less than 10 m( Omega )cm2. The deterioration test is performed by immersing titanium or titanium alloy material in sulfuric acid solution containing 2 ppm fluoride ions maintained at temperature of 80 degrees C and pH of 3 for four days, or applying electric potential of 1 V with respect to sulfuric acid solution at temperature of 80 degrees C and pH of 3 for 24 hours.