The propagation of ultrashort inten se laser pulses in the atmosphere will have many important applications in the fields such as remote sensing, electronic countermeasures and induced electric discharges. For instance, localized ultraviolet radiation induced at a remote distance can provide a source for fluorescence spectroscopy in the atmosphere. The physics of ultrashort intense laser pulses propagation in the atmosphere is described theoretically. In this paper, the linear effects and nonlinear effects are discussed, such as dispersion, self !focusing, stimulated Raman scattering, multiphoton ionization and tunneling ionization, pulse energy depletion due to ionization, relativistic focusing, and ponderomotively excited plasma wakefields, etc. The presented equation describing ultrashort intense laser pulses propagation in the atmosphere provides a basis for the future study.