Quasi-isotropic strands made of second generation (2G) wires are regarded as promising cables for large high field magnets in virtue of their high current capacity and well mechanical property. During the charge of the magnet, quasi-isotropic strands in use will subject to magnetic field and inevitably produce alternating current (AC) loss, which has important impacts on the magnet operation. This paper mainly presents the AC loss numerical simulation of a quasi-isotropic strand stacked by 2G wires under high magnetic field in cryogenic temperature. The strand with copper sheath consists of 72 assembled 2G wires. The numerical simulation is based on the H-formulation solved using the finite element method (FEM). The dependence of the critical current density on temperature and magnetic field as well as its orientation to wide surface of 2G wire is used in simulation. The AC loss mainly includes hysteresis losses, eddy-current losses and coupling losses. The angular dependence of AC loss of the strand on magnetic field is also estimated. The simulation results is helpful for overall understanding of the AC loss characteristics of the quasi-isotropic strand in high magnetic field.