Correlated evidences about the newest activity of Red River Fault in Vietnam (RRFV), such as seismicity, geology, geomorphology and chronology etc, have been obtained through joint survey along the fault in Vietnam. The comprehensive studies demonstrate that, the same tendency of gradual weakening of the fault activity from north to south in the part of China since Quaternary has been kept on in Vietnam. The primary active period of Red River Fault in Vietnam is in late of middle Pleistocene, and in general, the active level of Red River Fault is lower prominently than that in Yunnan Province, China, especially, the activity of RRFV has been very weak since late Pleistocene. The synthesized analysis on seismicity and regional GPS deformation monitoring data indicates that the dynamic impact of so-called lateral extrusion from Tibetan Plateau on the dextral slip of RRFV should be very limited.