Analysis some key problem about the chosen of upper limit order and order-determining rule. Then, predict the TEC by using linearity least variance prediction method and correcting prediction method. 对建立模型过程中阶数上限的确定及定阶准则的选取等关键问题进行了分析,分别采用线性最小方差预测法和修正预测法进行了预报。