The invention relates to the technology of signal emission and discloses a method for adjusting signal transmitting power and a mobile terminal. The method comprises following steps of: acquiring a back-off power parameter; modifying preset standard power values corresponding to power grades according to the back-off power parameter in order to generate back-off power values corresponding to the power grades, wherein the back-off power values are modified standard power values; and setting a current signal transmitting power value according to the back-off power values corresponding to the power grades and a current power grade, wherein the current signal transmitting power value is the back-off power value corresponding to the current power grade. The method for adjusting signal transmitting power and the mobile terminal enable a user to be capable of initiatively adjusting the signal transmitting power of the mobile terminal so as to reduce electromagnetic wave radiation on human bodies.