A method for protecting an application program password of a mobile terminal having a touch screen, comprising: obtaining a currently activated application interface view in an application program of a mobile terminal (S 110), wherein the currently activated application interface view is an application interface view selected from one or more application interface views displayed on the touch screen by a touch operation; determining whether the currently activated application interface view is an input box; and if yes, acquiring a key input event triggered in the input box; obtaining at least one character input in the input box by using the key input event; and replacing each of the at least one character with a fake password character, wherein the step of acquiring a key input event triggered in the input box and obtaining an input character by using the key input event comprises: obtaining through listening the key input event triggered in the input box, and positioning a location of a cursor in the input box according to the key input event obtained through listening; and acquiring a character input at the location of the cursor, and storing the input character according to the location of the cursor, wherein the character input is acquired according to an input manner selected from the list consisting of a soft keyboard input manner and a hard keyboard input manner, wherein in the hard keyboard input manner, the location of the cursor is acquired by reloading a dispatchKeyEvent function to acquire the character input, and wherein in the soft keyboard input manner, an InputConnection input channel is newly established, the newly established InputConnection input channel and a currently triggered key input event are bound, and the currently triggered key input event is processed by using the newly established InputConnection input channel, in which case, system functions such as commintText, sendKeyEvent, setComposingText and finishComposingText are reloaded to acquire the character input. obtaining a currently activated application interface view in an application program of a mobile terminal (S 110), wherein the currently activated application interface view is an application interface view selected from one or more application interface views displayed on the touch screen by a touch operation; determining whether the currently activated application interface view is an input box; and if yes, acquiring a key input event triggered in the input box; obtaining at least one character input in the input box by using the key input event; and replacing each of the at least one character with a fake password character, wherein the step of acquiring a key input event triggered in the input box and obtaining an input character by using the key input event comprises: obtaining through listening the key input event triggered in the input box, and positioning a location of a cursor in the input box according to the key input event obtained through listening; and acquiring a character input at the location of the cursor, and storing the input character according to the location of the cursor, wherein the character input is acquired according to an input manner selected from the list consisting of a soft keyboard input manner and a hard keyboard input manner, wherein in the hard keyboard input manner, the location of the cursor is acquired by reloading a dispatchKeyEvent function to acquire the character input, and wherein in the soft keyboard input manner, an InputConnection input channel is newly established, the newly established InputConnection input channel and a currently triggered key input event are bound, and the currently triggered key input event is processed by using the newly established InputConnection input channel, in which case, system functions such as commintText, sendKeyEvent, setComposingText and finishComposingText are reloaded to acquire the character input. obtaining through listening the key input event triggered in the input box, and positioning a location of a cursor in the input box according to the key input event obtained through listening; and acquiring a character input at the location of the cursor, and storing the input character according to the location of the cursor, wherein the character input is acquired according to an input manner selected from the list consisting of a soft keyboard input manner and a hard keyboard input manner, wherein in the hard keyboard input manner, the location of the cursor is acquired by reloading a dispatchKeyEvent function to acquire the character input, and wherein in the soft keyboard input manner, an InputConnection input channel is newly established, the newly established InputConnection input channel and a currently triggered key input event are bound, and the currently triggered key input event is processed by using the newly established InputConnection input channel, in which case, system functions such as commintText, sendKeyEvent, setComposingText and finishComposingText are reloaded to acquire the character input.