An ultra-low quiescent current resistor-less power on reset circuit is presented in this brief. The circuit is used in energy harvesting systems to change boost converter from startup state to PWM modulation state. It integrates power on reset (POR) and brown out detection (BOD) functions without resistors or bandgaps overhead. Dual threshold detection (DTD) technology is used instead of a large size delay cell in generation of pulse signals. The circuit has been implemented in a 0.13μm standard CMOS technology. The active area and the quiescent current of the circuit are 154.4μm x 26.8μm and about 1nA, respectively. Ultra-low quiescent current and small area make the proposed circuit suitable to be applied in low power applications like energy harvesting and beyond.