  We present two groups of practical entanglement concentration protocols
(ECPs) for optical hybrid entangled state (HES). In the first group, it
contains two ECPs and both ECPs do not need to know the initial coefficients of
the less-entangled state. The second group contains three ECPs and they need to
know the initial coefficients. It is shown that the yield of the entanglement
concentration in the second group is greater than the first group. Moreover,
some protocols are based on the linear optics and can be easily realized under
current experiment condition. These protocols may be useful in current hybrid
quantum communication.
