Carbon　nanorods　and　graphene-like　nanosheets　are　catalytically　synthesized　in　a　hot　filament　chemical　vapor　deposition　system　with　and　without　plasma　enhancement,　with　gold　used　as　a　catalyst.　The　morphological　and　structural　properties　of　the　carbon　nanorods　and　nanosheets　are　investigated　by　field-emission　scanning　electron　microscopy,　transmission　electron　microscopy　and　micro-Raman　spectroscopy.　It　is　found　that　carbon　nanorods　are　formed　when　a　CH4　+　H-2　+　N-2　plasma　is　present　while　carbon　nanosheets　are　formed　in　a　methane　environment　without　a　plasma.　The　formation　of　carbon　nanorods　and　carbon　nanosheets　are　analyzed.　The　results　suggest　that　the　formation　of　carbon　nanorods　is　primarily　a　precipitation　process　while　the　formation　of　carbon　nanosheets　is　a　complex　process　involving　surface-catalysis,　surface　diffusion　and　precipitation　influenced　by　the　Gibbs-Thomson　effect.　The　electron　field　emission　properties　of　the　carbon　nanorods　and　graphene-like　nanosheets　are　measured　under　high-vacuum;　it　is　found　that　the　carbon　nanosheets　have　a　lower　field　emission　turn-on　than　the　carbon　nanorods.　These　results　are　important　to　improve　the　understanding　of　formation　mechanisms　of　carbon　nanomaterials　and　contribute　to　eventual　applications　of　these　structures　in　nanodevices.