We　present　a　simple　method　of　realizing　controlled　hole　burning　for　a　cavity　mode　in　Fock　space　by　using　a　single　two-level　atom.　In　the　scheme,　the　atom　is　driven　by　a　classical　field　and　dispersively　interacts　with　the　cavity　mode.　Due　to　the　photon　number-dependent　atomic　transition　frequency　shift,　the　atom　is　excited　only　for　a　specific　Fock　state.　As　a　result,　the　detection　of　the　atom　remaining　in　the　ground　state　projects　the　cavity　to　the　state　with　a　desired　hole　in　Fock　space.　An　important　feature　of　the　scheme　is　that　multiple　holes　can　be　burnt　at　the　same　time　with　a　single　atom　driven　by　a　pulse　composed　of　multiple　frequency　components.