The paper a naly zes the speciali ties of the vast terri to ry and sparse populatio n of the Xi zang regio n, i ts special market eco nomy and complex to pog raphic and g eologic co ndi tions. Based on the compariso ns o f the main const ructio n engineering w o rks betw een the Kunming-Yiping lang qeter-g aug e and standard-g aug e railw ays, the author proposes his o pinio ns co ncerned w ith the sugg estio n fo r constructing the electrified lig ht ( meter-g aug e) railw ay s in the Xi za ng regio n instead o f the standard-gaug e rai lway s.