For the purpose of viscosity measurements of hydrogen at high pressures and high temperatures, a new system with the vibrating wire method that requires only a small amount of sample was developed for the viscosity measurements at low pressures below 1 MPa. The vibrating wire method is the way to supply current to a wire set in the magnetic field and determine the viscosity of the sample fluid by the oscillation of the wire. A curved semi-circle wire made of tungsten and samarium cobalt magnets were adopted in this study. The internal friction coefficient, an important apparatus constant, was measured first at room temperature and 50°C under 1 MPa. Then, the viscosities of nitrogen, helium, and hydrogen were measured under the same conditions.