Abstract: In order to compare the differences of response to proinflammatory reaction induced by mainstream cigarette smoke among cells of different types, neutral red uptake (NRU) assay was employed to assess the cytotoxicity of cigarette smoke total particulate matter (TPM) or whole smoke (WS) to A549 cells (human adenocarcinoma cells) and BEAS-2B cells (human bronchial epithelial cells). The levels of proinflammatory cytokines interleukin-6 and interleukin-8 (IL-6 and IL-8) released from A549 and BEAS-2B cells exposed to TPM and WS were analyzed by ELISA. The results showed that BEAS-2B cells were more sensitive to smoke-induced cytotoxicity than A549 cells. The induction of IL-6 and IL-8 released from A549 cells was not impacted by cigarette smoke exposure, while TPM and WS all caused dose-dependently increase of IL-6 and IL-8 released from BEAS-2B cells. The proinflammatory response to cigarette smoke thus might be different depending on cell types.