Abstract:Based on the analysis of recent situation of the existing railway networks in Southwest China, the basic principles which should be followed in construction of railway networks in Southwest China arc proposed. The preliminary tentative plan concerned with establishing the structural frame for the railway networks in Southwest China has been proposed, and expounded emphatically in following three aspects: (1) constructing Lanzhou-Kunming extra-long railway passage to enhance the connection between Northwest China and Southwest China, (2) constructing Pan-Asia Railway to open up the international railway passage, and (3) constructing the railways towards Xizang. Several suggestions are proposed also in this paper.