Polarization of the valence, nonstrange, and strange quarks in the nucleon determined by COMPASS

The results of quarks helicity distributions are presented which were determined by COMPASS experiment at CERN. Different approaches have been accomplished in order to access various sets of quarks distributions. The analysis of spin structure function $g_{1}$ gives information about contribution to the spin of the nucleon from sum of quarks. From method of difference asymmetry for hadrons with opposite charges one can learn about polarized valence quark distributions. Finally, a recent analysis of full avour separation was presented in Quark Parton Model (QPM) and LO QCD approximation. All analyses have been done in perturbative regime Q$^{2} >$ 1 (GeV/c)$^{2}$.