A pyrohydrolysis method has been developed for separating percentile level boron in borated Zr-Nb alloy. The pyrohydrolytic behaviour of this alloy was studied and the optimum separation conditions required for achieving complete recovery of boron were identified. Zr-Nb alloy turnings (thickness < 0.1 mm) were subjected to pyrohydrolysis at 1,230°C for 120 min with moist oxygen carrier gas at a flow rate of 2 L/min. The pyrohydrolysis distillates were analysed by ion chromatography (5 mM NaOH and d-mannitol as eluent) for boron quantification. The method showed an external precision better than 2.5%.