A viscoelastic characteristic value-measuring apparatus, using a split Hopkinson's bar, having an impact bar, input bar, and an output bar. The input bar has a first strain gauge and a second strain gauge. The output bar has a third strain gauge and a fourth strain gauge. The input bar and the output bar are made of a viscoelastic material, and a specimen is in between the input bar and the output bar. The length of said output bar is set to a range from 500 mm to 2500 mm both inclusive. The length of said input bar is set to a range from 1500 mm to 2500 mm both inclusive.