Based on the actual data of Xiushan County and Chinese manganese demand, GM (1, 1) model was established to predict the manganese demand. The prediction accuracies of Xiushan’s manganese demand, Chinese manganese production and exports were respectively 95.5%, 94.5% and 96.3%. Residual error test showed that the model was reliable and could be used to predict the manganese demands in the future five years. And the demands would be grown exponentially with time. The predictive results indicated that the supply safeguard was worrying.