Induced pluripotent stem (iPS) cells are a type of pluripotent stem cell artificially derived from a non-pluripotent cell by inducing a "forced" expression of specific genes and cellular dedifferentiate.iPS cells attract enormous attention due to their potential in understanding disease mechanism and developing regenerative medicine.Although cells show similar function and physiology to natural pluripotent stem cells in many respects, such as the expression of certain stem cell genes and proteins, but the full extent of their relation to natural pluripotent stem cells is still being assessed, and many questions need to be better understood, especially in dynamics of epigenetic codes during reprogramming.Histone post-translational modifications (PTMs) have been considered to be important epigenetic marks.Ten types of histone PTMs had been described in diverse DNA-templated processes.