The basic problems of neotectonics in Hengduan Mountain System are summarized as follows:
1) neotectonic period and relations between neotectonic period and Himalayan period.
2) the shape types of neotectonics and the movemental types of neotectonics.
3) neotectonic inheritance.
4）strength and trend of neotectonic movement.
5) resources effects of neotectonic movement
6) environmental effects of neotectonic movement.
7) neotectonic strees field and driving mechanism
8) neotectonic orogenesis and the formation of Hengduan Mountain System.

In Hengduan Mountain System. the limit of neotectonic movement is determined by the desintegration of paleoplanation surface in wide area. Xigeda Formation Which is the earlist sediments 、in graben basin and a angular unconformity to Precenozoic or Eogene System. The present relief in this region is developed following block-faulting movemnt on the basis of paleoplanation surface. The block - faulting period is the neotectonic period . The lower boundary of the neotectonic p盯iod corresponds to Gauss/Gilbert in the paleomagnetic chronological scale of Late Cenozoic. which is 3. 4 Ma BP. or so. The lacuna under the boundary to Late Miocene shows that there is a paleoplanation period. The hiatuses and unconformities above the boundary show that the fluctuation of neotectonic movement is frequent.
The boundary is starting point in studying the basic problems of neotectonics .

Mts. Hengduan is a S-N tectonic zone composed of (from west to east) Himalaya folding belt. Yanshan folding belt. 1ndo-Sinain folding belt and a part of South-West China Platform. and come down in one continous line with E-W tectonics in Tibetan Plateau. constructing a huge arcuate tectonic system in continent. According to the amount of data. this tectonic system has undergone many times of orogenic-planation cycles; until the late Pliocene. it was planned off to form a peneplain. On this basis. with the upwarping of Tibetan Plateau. the transitional area at the front part of the plateau was subjected to strong erosion. leading the formation of Mts. Hengduan. Accordingly. Mts. Hengduan is a neotectonic orogenic belt resulted from block upwartping-erosion in continent rather than folding reversion in geosynclinal area. Even in the recent. 1ndia Plate is continually moving north , ward. and Tibetan Plateau is still under its sustained compression. As a fact. Mts. Hengduan has also been in the upwarping state by now.