Abstract: Visualization experiments and the PSD of pressure signal were used to identify cryogenic vaporliquid two phase flows regime in vertical pipes. The flow regime got from highspeed camera and one inferred according to the PSD of pressure signal of different location were compared. It is found that PSD which is usually used to identify room temperature two phase regime can also be used to identify cryogenic two phase flow regime; even in different heat flux, it all works.