Alternative test methods have been developed for various areas of toxicologic evaluation including skin sensitization or irritation, eye irritation, genotoxicity, or carcinogenicity. Whereas, alternative test method, especially based on in vitro approach, for screening immunotoxic substances was not actively challenged and therein, no test guideline has not been officialized internationally. THP-1 dendritic cell line was chosen for developing in vitro alternative test method for screening immunotoxic chemical or medicinal substances. Regarding major pathway for immune suppression or non-specific immune enhancement, antigen presenting cell is considered as most important target immune cells. Two test substances representing immune-enhancement(ribavirin) or immune-suppression (cyclophosphamide) were tested whether production of cytokines or chemokines is differentially modulated through supplementation of 0.01x, 0.1x, and 0.5x 75% cell viability(CV75) concentration of those compounds. Cell culture supernatants were collected at 24 h after the activation with 1 ㎍/㎖ lipopolysaccharide. Relative cytokine production levels (% versus each vehicle control, RCPL) were calculated. Production of all 27 cytokines evaluated was confirmed, which included IL-1β, IL-1ra, IL-2, IL-4, IL-5, IL-6, IL-7,IL-8, IL-9,IL-10, IL-12, IL-13, IL-15, IL-17, Eatoxin, FGF basic, G-CSF, GM-CSF, IFNγ, IP-10, MCP-1, PDGF-BB, MIP-1α, MIP-1β, RANTES, TNFα, VEGF. Treatment of ribavirin demonstrated all the RCPL values over 100% at 0.01x and 0.1x CV75 concentration. Treatment of cyclosphosphamide demonstrated the RCPL values below 100%except IL-12(0.01x), IL-13(0.1x), MCP-1(0.01x), TNFα (0.01x, 0.1x, and 0.5x), and VEGF(0.01x, 0.1x, and 0.5x). This findings suggest that THP-1 cell line is a valuable cell line to develop an in vitro alternative test method for screening immunotoxic chemical substances.