We investigated angle-resolved optical parametric generation (OPG) in 2D periodically poled lithium tantalate (PPLT) with a 8.52 μm square lattice structure. Substantial parametric gain was observed at two specific incident angles of and , with the signal/idler wave propagating collinearly/non-collinearly to a 532 nm pump. These phenomena are due to simultaneous quasi-phase-matching OPG processes involved contribution from the reciprocal lattice vectors of ( and ) or ( and ), respectively. These configurations raise the parametric gain to comparable to that of the 1D QPM structure.