  We discuss the results of our recent analysis [1] of deep inelastic
scattering data on F2 structure function in the non-singlet approximation with
next-to-next-to-leading-order accuracy. The study of high statistics deep
inelastic scattering data provided by BCDMS, SLAC, NMC and BFP collaborations
was performed with a special emphasis placed on the higher twist contributions.
For the coupling constant the following value alfa_s(MZ2) = 0.1167 +- 0.0022
(total exp. error) was found.
