Analytical method and analytical system are presented, wherein properties of the carrier gas conveying fine particles and gas components generated by laser ablation can be prevented from inhibiting the optimization of analysis conditions, and plural kinds of elements can be stably measured with high sensitivity and good accuracy without losing operability, speed, and convenience when fine particles generated by laser ablation are plasma-analyzed. A sample α is converted into fine particles by a laser ablation device in the atmosphere of a first gas. The fine particles are conveyed from the laser ablation device to a gas replacement device by using the first gas as a carrier gas. The first gas of at least part of the carrier gas conveying the fine particles is replaced with a second gas by means of the gas replacement device. The fine particles are conveyed from the gas replacement device to the plasma analyzer by the carrier gas that has been subjected to the gas replacement. Constituent elements of the fine particles are analyzed by the plasma analyzer.