The present invention discloses a combined-source MOS transistor with a Schottky Barrier and a comb-shaped gate structure, and a method for manufacturing the same. The combined-source MOS transistor includes: a control gate electrode layer, a gate dielectric layer, a semiconductor substrate, a highly-doped source region and a highly-doped drain region, wherein a Schottky source region is connected to a side of the highly-doped source region which is far from a channel, one end of the control gate extends to the highly-doped source region, the extended gate region is an extension gate in a form of a comb-shaped and the original control gate region is a main gate; an active region covered by the extension gate is also a channel region, and is a substrate material; the highly-doped source region which is formed by highly doping is located on both sides of each comb finger of the extension gate; and a Schottky junction is formed at a location where the Schottky source region and the channel under the extension gate are located. As compared with an existing MOSFET, in the invention, a higher turn-on current, a lower leakage current and a steeper subthreshold slope may be obtained under the same process condition and the same active region size.