Laser irradiation to gaseous molecules, such as carbon disulfide, is known to form particles floating in the vapor. These particles are called aerosol. This reaction system is open in view of energy and material fluxes. The energy is constantly supplied to the reaction system by laser irradiation and consumed in photochemical processes. The reactant is supplied to the reaction region by diffusion flux and the product, i.e. aerosol, is removed by sedimentation. Thermodynamic conception for nonequilibrium system suggests the possibility of the formation of the dissipative structure in suchlike open system. In fact, in the present study, the self-organization, represented by oscillations, aerosol burst, aerosol echo, etc., is confirmed in the aerosol formation from CS₂ vapor by N₂-laser irradiation: The reaction system departs from the initial state by the laser irradiation, then oscillatorilly or nonoscillatorilly, depending on the reaction condition, approaches the steady state. This oscillation is called Type-I. Besides, we can observe the Type-II oscillations with higher frequencies. This oscillation is accounted due to the fluctuation of the aerosol concentration at each local reaction site. The intense periodic Type-II oscillations, called aerosol burst, can be observed. The characteristics of the aerosol burst are similar to those of the nonlinear coupling of oscillators. This indicates that aerosol burst is due to the nonlinear coupling of the oscillation of the aerosol concentration at each local site. In aerosol burst, the system fluctuately moves on the hierarchical orbit consisting of principle limitcycles and sublimitcycles. This fluctuation-like phenomenon is essentially deterministic, since the fragments of the attractor are observed. Aerosol echo is observed after the stop of the laser irradiation. That is, the aerosol concentration decreases first, and then increases once, followed by the decrease to zero. It is due to the aerosol formation by coagulations of aerosol precursors and active molecular species that remain in the reaction system.