Ten cases of hematuria in Grant's gazelle (Gazella granti) (two male and eight female) from five institutions were examined and the clinicopathologic data summarized. Five gazelles died spontaneously and five were euthanized. All gazelles had marked hematuria without pyuria. Mean age at the onset of clinical signs and time of euthanasia or death was 5.0 ± 1.4 yr and 8.2 ± 3.7 yr, respectively. The severity of clinical signs with hematuria ranged from episodes of chronic intermittent hematuria to marked dysuria, with urinary bladder rupture secondary to obstructive blood clots in one case. Submandibular edema was the most common associated clinical sign (five of 10 cases). Serum chemistries from eight gazelles obtained during hematuria episodes revealed hypocalcemia (8/8), hypoproteinemia (7/8), hypoalbuminemia (7/8), and hyperphosphatemia (6/8). Fifty percent of the gazelles (4/8) developed anemia over the course of hematuria episodes. Prothrombin times and partial thromboplastin times were presumed increased in two of four animals evaluated. The predominant histologic lesions in seven of 10 gazelles reviewed were vascular necrosis, vasculitis, and perivasculitis in the urinary tract. Lesions in necropsied gazelles were identified in the urinary bladder (7/10 gazelles), kidney (3/10), and ureter (3/10). Additional urinary tract lesions included tubulointerstitial nephritis (5/10 gazelles), hemorrhagic cystitis (4/10), renal tubular necrosis (4/10), and subacute renal infarcts (2/10). Polymerase chain reaction testing on paraffin-embedded urinary tract tissue for alcelaphine herpesvirus-1 and -2, ovine herpesvirus-2, bluetongue virus, and epizootic hemorrhagic disease virus was negative for the six cases tested. One gazelle that had been vaccinated for Leptospira interrogans had a titer to serovar icterohaemorrhagiae, but serum from the six other gazelles tested was negative for all L. interrogans serovars. No exposure to any toxic agent was identified. An underlying cause for vascular lesions associated with episodic hematuria in Grant's gazelles remains to be determined.