[en] A new class of the gauge fixing conditions - contour gauges - is introduced. It is shown that in the case of the simplest straioht line contours the contour gauges reproduce the well-known ghost-free gauges. Using the contour gauge technique enables us to find a relation between the end-point and cusp singularities of the contour averages. On the basis of an analysis of the particular contour average absorbing all the infrared singularities of the on-shell quark form factor it is demonstrated that its IR singularities are in a one-to-one correspondence with its UV-singularities, and consequently, it has been established that one can use the renormalization group methods for studying the IR asymptotics of the QCD amplitudes. The relevant anomalous dimension was calculated to order a sub(s). The method can be applied to study the IR asymptotics of various QCD processes