The time-resolved spectra of the air-breakdown plasma generated by the nanosecond pulsed 1064 nm beam of a Nd:YAG laser are investigated by using a PI-MAX-II ICCD with nano-time-resolved features. The results show that the laser-induced plasma spectrum in atmospheric environment is widely distributed in a range of 300-900 nm, and it is superimposed by continuous spectra and sharp line spectra. The spectral lines of oxygen, nitrogen and hydrogen are identified according to the National Institute of Standards and Technology database of atomic emission. The intuitive figures of laser-induced breakdown atmospheric plasma spectra with time resolution are given. The electron temperature and electron density are calculated according to the emission spectra. The results have scientific significance for improving the accuracy and precision of the on-line measurement in the atmospheric environment.