  We calculate the viscous pressure tensor of the quark-gluon plasma in strong
magnetic field. It is azimuthally anisotropic and is characterized by five
shear viscosity coefficients, four of which vanish when the field strength eB
is much larger than the plasma temperature squared. We argue, that the
azimuthally anisotropic viscous pressure tensor generates the transverse flow
with asymmetry as large as 1/3, even not taking into account the collision
geometry. We conclude, that the magnitude of the shear viscosity extracted from
the experimental data ignoring the magnetic field must be underestimated.
