Abstract:The southeast margin of Aljin mountains in Chaidam basin experienced multi-period structural movement in geologic history,resulted in complex structures.It is showed in the paper by studying faults and structural style that abnormal fault de-veloped in the southeast margin of Aljin moun-tains,which formed"brush"distribution that dis-persed toward the piedmont of Aljin mountains and converged toward the basin;a series of faulted noses and multiple structural styles are formed un-der the controlling of the press-shear faults,result-ed in large difference between deep and shallow structures.It is considered by integrative analysis and evaluation for source rock,reservoir and cap that the conditions of source rock,reservoir and cap are very good,the Jurassic has hydrocarbon-generated potential,traps developed,the type of reservoir is rich and great potentialities of explo-ration existed.The resulted conclusions have cer-tain guided meaning to further carry out oil/gas exploration in the southeast margin of Aljin mountains.