The invention relates to a low dropout linear voltage regulator (LDO) without an off-chip capacitor for improving transient response and increasing power supply rejection ratio (PSRR). The LDO without the off-chip capacitor comprises an error amplifier, a reference voltage source module, a power adjusting tube, an NMC Miller's compensating circuit, a PSRR enhanced network and a transient response intensifier circuit. According to the LDO without the off-chip capacitor, the NMC compensation technique is used for meeting the system stability requirement; a second-stage gm improved circuit of the amplifier is used for increasing the charging and discharging currents to the grid of the power tube; a slew rate intensifier circuit is introduced, needed currents can be provided for a load when the load of the LDO is subjected to step hopping from small to large, and thus the transient response capacity of the LDO is improved under the double actions. In addition, the PSRR enhanced network is additionally arranged to be used for controlling the PSRR feedback factors beta of the system, an original zero point is pushed to the position with higher frequency, and therefore the PSRR characteristic of the system is improved. The LDO without the off-chip capacitor is improved on the aspect of transient response and the aspect of PSRR.