We investigate the existence of a single-∧ hyperon halo in 15 3∧ C and a two-∧ hyperon halo in 16 4∧Ground-state properties of hyperon carbon isotopes, such as density distributions, single particle levels in the canonical basis,the binding energy, ∧ separation energy and radii, are calculated and discussed by using the relativistic continuum Hartree-Bogoliubov theory. The hyperon halo phenomenon in 15 C and 16 4∧ C and 16 4∧C is supported by the discussion of the weakly bound state 1p3/2, extended density distribution and small separation energy of the ∧ hyperon.