This paper reports the characteristics of hydrothermal breccia discovered recently, their hydrothermal karst as well as associated geological disasters in the Beiya area, western Yunnan province. The hydrothermal breccia and karst in the Beiya area are divided into 4 types and zones, including: ① sedimentary tuff and breccia induced by hydrothermal explosion and sedimentation on land surface; ② hydrothermal sedimentary conglomerate and gas-explosive ejecting breccia related to sedimentation in and collapsing of some shallow karst caves; ③ netted hydrothermal limestone breccia and hydrothermal explosive breccia pipe related to hydrofracturing, corrosion and explosion in the hydrothermal channels; and ④ yellow granular limestone formed by simmering and alteration in the deep heated water reservoir. Except the simmering in deep area, other three kinds of hydrothermal karst would associate and induce geological disasters. The hydrothermal limestone breccia sheet presented over Tertiary fluvial, lacustrive sandstone and mud in the Wandongshan-Wulipai area is a hydrothermal breccia landslide from the Chenjiazhuang breccia pipe, and it may be a domain origin which would have obstructed the Jinshajiang old channel and made the Jinshajiang river to change and to form the famous valley and turns.