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Two TiAl alloys, Ti–47.5Al–3.7(Cr, V, Zr) and Ti–47.5Al–3.7(Cr, V, Zr)–0.1C (at.％), were prepared by cold crucible levita-tion melting to couple the hard-oriented directional lamellar microstructure with carbon microalloying strengthening. The creep behavior and mechanism for the improvement in creep properties by carbon addition were investigated by mechani-cal tests and electron microscopy characterizations. The results show that obvious improvements on the creep properties at 760℃ and 276 MPa are achieved by 0.1 at.％ C addition into TiAl alloy with directional lamellar microstructure, which promotes the creep strain and minimum creep rate decreasing with a large content. The minimum creep rate is reduced from 4.37?×?10?8 to 3.97?×?10?9 s?1, and the duration entering into creep acceleration is prolonged for more than 10 times. The mechanism for creep property improvement by 0.1％ C addition is attributed to two aspects. The first one is that -Ti2AlC is found to be strong obstacles of 1/2[110] dislocations when moving across the lamellar interface in the carbon contain-ing alloy. The other one is that the interfacial dislocations are effectively impeded and the release process is hindered by dynamic precipitation of -Ti3AlC, which is proposed to be the special mechanism for creep resistance improvement of this hard-oriented directional lamellar microstructure.