Laser applications of nonlinear optical (NLO) crystals are limited by their laser damage threshold. We report a detailed study of the laser damage threshold of an NLO crystal glucuronic acid -lactone. Second-harmonic generation efficiency of glucuronic acid -lactone was estimated to be 3.5 times that of standard potassium dihydrogen phosphate. Conic sections due to spontaneous noncollinear phase matching were observed. Surface laser damage studies carried out for 1064-nm radiation on a (010) plate of the crystal yielded high-threshold values of and for single- and multiple-shot damages, respectively. The possible mechanisms for the laser-induced damage are discussed.