Disclosed is a silicon single crystal pull-up apparatus that can grow a silicon single crystal having a desired electrical resistivity, to which a sublimable dopant has been reliably added, regardless of the length of the time necessary for the formation of a first half part of a straight body part in a silicon single crystal. Also disclosed is a process for producing a silicon single crystal. The silicon single crystal pull-up apparatus pulls up a silicon single crystal from a melt by a Czochralski method. The silicon single crystal pull-up apparatus comprises a pull-up furnace, a sample chamber that is externally mounted on the pull-up furnace and houses a sublimable dopant, a shielding mechanism that thermally shields the pull-up furnace and the sample chamber, and supply means that, after the release of shielding of the shielding mechanism, supplies the sublimable dopant into the melt.