Charge-trapping properties of Nb-doped $\hbox{La}_{2}\hbox{O}_{3}$ (LaNbO) are investigated using an $\hbox{Al/Al}_{2}\hbox{O}_{3}/\hbox{LaNbO/SiO}_{2}/\hbox{Si} $ structure. Compared with the memory device with $\hbox{La}_{2}\hbox{O}_{3} $, the one with LaNbO shows better charge-trapping characteristics, including larger memory window (6.0 V at $\pm \hbox{16} $ V sweeping voltage), higher programming speed (9.1 V at $+\hbox{16} $ V for 1 ms), and better retention property (94% charge retained after $\hbox{10}^{4}$ s at $\hbox{120}\ ^{\circ}\hbox{C} $) , due to its higher trapping efficiency resulted from increased trap density and suppressed formation of a silicate interlayer at the $\hbox{LaNbO/SiO}_{2} $ interface by the Nb doping. Therefore, LaNbO is a promising candidate as the charge-trapping layer for nonvolatile memory applications.