  Recently, Zhao et al., (Int. J. Theor. Phys. 57, 516-522 (2018)) have
proposed a scheme for quantum teleportation of an eight-qubit quantum state
using a six qubit cluster state. In this comment, it's shown that the quantum
resource (multi-partite entangled state used as the quantum channel) used by
Zhao et al., is excessively high and the task can be performed using any two
Bell states as the task can be reduced to the teleportation of an arbitrary two
qubit state. Further, a trivial conceptual mistake made by Zhao et al., in the
description of the quantum channel has been pointed out. It's also mentioned
that recently a trend of proposing teleportation schemes with excessively high
quantum resources has been observed and the essence of this comment is
applicable to all such proposals.

Quantum Physics