  One of the goals of the COMPASS experiment is the determination of the gluon
polarisation \Delta G/G, for a deep understanding of the spin structure of the
nucleon. In DIS the gluon polarisation can be measured via the
Photon-Gluon-Fusion (PGF) process, identified by open charm production or by
selecting high p_T hadron pairs in the final state. The data used for this work
were collected by the COMPASS experiment during the years 2002-2004, using a
160 GeV naturally polarised positive muon beam scattering on a polarised
nucleon target. A new preliminary result of the gluon polarisation \Delta G/G
from high p_T hadron pairs in events with Q^2>1 (GeV/c)^2 is presented. In
order to extract \Delta G/G, this analysis takes into account the leading
process \gamma q contribution together with the PGF and QCD Compton processes.
A new weighted method based on a neural network approach is used. A preliminary
\Delta G/G result for events from quasi-real photoproduction (Q^2<1 (GeV/c)^2)
is also presented.
