An on-chip nanopower RC relaxation oscillator is developed in a 180-nm standard CMOS process, consuming 300 nW while running at 10 kHz. Employing a frequency compensation scheme that reduces the frequency drift introduced by comparator offset and delay, the proposed oscillator achieves a significant low temperature coefficient. Furthermore, a supply regulation structure is used to reduce the frequency sensitivity to supply voltage variations. Post-simulation results show that the frequency variation against temperature is 105 ppm/C in the temperature range from 0 to 85 C, and the line sensitivity is 2.19%/V with the supply voltage changing from 1.05 to 1.45 V. At offset frequencies of 100 Hz and 1 kHz, the simulated phase noises are −50 and −71 dBc/Hz, respectively.