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Due to substantial phonon scattering induced by various structural defects, the in‐plane thermal conductivity (K) of graphene films (GFs) is still inferior to the commercial pyrolytic graphite sheet (PGS). Here, the problem is solved by engineering the structures of GFs in the aspects of grain size, film alignment, and thickness, and interlayer binding energy. The maximum K of GFs reaches to 3200 W m⁻¹ K⁻¹ and outperforms PGS by 60%. The superior K of GFs is strongly related to its large and intact grains, which are over four times larger than the best PGS. The large smooth features about 11 µm and good layer alignment of GFs also benefit on reducing phonon scattering induced by wrinkles/defects. In addition, the presence of substantial turbostratic‐stacking graphene is found up to 37% in thin GFs. The lacking of order in turbostratic‐stacking graphene leads to very weak interlayer binding energy, which can …