The invention provides an energy absorption device obtaining method and obtaining device. The energy absorption device obtaining method comprises the following steps of obtaining the dimension of a space to be installed; obtaining a first energy absorption device matched with the space to be installed from an energy absorption device database according to the dimension of the space to be installed; then, outputting the information of the first energy absorption device. According to the technical scheme, a user can automatically obtain the first energy absorption device matched with the space to be installed from the energy absorption device database according to the space to be installed of the energy absorption device; further, the work burden of the user for designing the energy absorption device is reduced; the production period of the energy absorption device is shortened; the production cost of the energy absorption device is reduced.