A method for charging a terminal comprising two batteries, comprising: acquiring (101, 201) remaining electric quantities in the two batteries; performing (102, 202) a trickle-current charging and a constant-current charging on a first battery of the two batteries in sequence when the remaining electric quantities in the two batteries are less than a preset value; wherein the method is characterized by: stopping charging the first battery and supplying power by the first battery to a mainboard of the terminal when it is detected that a charging state of the first battery is changed from the constant-current charging to a constant-voltage charging, such that current input via an adapter is used to charge a second battery of the two batteries; performing the trickle-current charging and the constant-current charging on the second battery of the two batteries in sequence; stopping supplying power by the first battery to the mainboard of the terminal when it is detected that the constant-current charging for the second battery finishes, such that a part of the current input via the adapter is used to supply power to the mainboard; performing the constant-voltage charging on the two batteries simultaneously; and supplying power to the mainboard of the terminal by one of the two batteries whose remaining electric quantity reaches a threshold such that the adapter is prevented from applying directly power to the mainboard, and performing the constant-voltage charging on the other one of the two batteries whose remaining electric quantity is less than the threshold. acquiring (101, 201) remaining electric quantities in the two batteries; performing (102, 202) a trickle-current charging and a constant-current charging on a first battery of the two batteries in sequence when the remaining electric quantities in the two batteries are less than a preset value; wherein the method is characterized by: stopping charging the first battery and supplying power by the first battery to a mainboard of the terminal when it is detected that a charging state of the first battery is changed from the constant-current charging to a constant-voltage charging, such that current input via an adapter is used to charge a second battery of the two batteries; performing the trickle-current charging and the constant-current charging on the second battery of the two batteries in sequence; stopping supplying power by the first battery to the mainboard of the terminal when it is detected that the constant-current charging for the second battery finishes, such that a part of the current input via the adapter is used to supply power to the mainboard; performing the constant-voltage charging on the two batteries simultaneously; and supplying power to the mainboard of the terminal by one of the two batteries whose remaining electric quantity reaches a threshold such that the adapter is prevented from applying directly power to the mainboard, and performing the constant-voltage charging on the other one of the two batteries whose remaining electric quantity is less than the threshold. stopping charging the first battery and supplying power by the first battery to a mainboard of the terminal when it is detected that a charging state of the first battery is changed from the constant-current charging to a constant-voltage charging, such that current input via an adapter is used to charge a second battery of the two batteries; performing the trickle-current charging and the constant-current charging on the second battery of the two batteries in sequence; stopping supplying power by the first battery to the mainboard of the terminal when it is detected that the constant-current charging for the second battery finishes, such that a part of the current input via the adapter is used to supply power to the mainboard; performing the constant-voltage charging on the two batteries simultaneously; and supplying power to the mainboard of the terminal by one of the two batteries whose remaining electric quantity reaches a threshold such that the adapter is prevented from applying directly power to the mainboard, and performing the constant-voltage charging on the other one of the two batteries whose remaining electric quantity is less than the threshold.