To deal with the problem that autosorb analyzer can only work under the condition of pressure below 0.1 MPa, we have designed and fabricated a new apparatus which is used to study the characteristics of adsorption in an extended range of pressure.Ideal gas equation of state and van der Waals equation are used to calculate the capacity of hydrogen storage of the materials of resorcinol-formaldehyde carbonized aerogel with the help of the new apparatus.