Abstract: Gas drainage is the main measure for radical gas disaster prevention and control, and pipeline resistance calculation is the precondition for gas design and parameters optimization, however some errors are obviously between theory calculation and field testing at present. In order to analyze the friction resistance characteristics of drainage pipeline and optimize calculation method, the essence connotation and main affecting factors were discussed according as hydrodynamics Darcy's law and dimensional theory, and the deficiency of actual calculation method was pointed out, and optimization method was set up. Basing on above-mentioned analysis, optimization method was applied to scene practice contrasting primary one. The results showed that optimized method was accordant with testing result with comparative error 0.6% merely.