Reflection phase properties of one-dimensional photonic crystals (PhCs) with mu-negative or double-negative materials are investigated by the transfer matrix method. In both of the two structures-“mu-negative positive-index PhC” and “double-negative positive-index PhC”, the results show that the reflection phase in the omni-directional gap increases with the increase of incident angle for TE modes. For TM modes, the reflection phase decreases with the increase of incident angle. And the reflection phase increases with the increase of the scaling factor of layer thickness, while keeps invariant with the increase of periodic numbers for both TE and TM modes.