To elucidate anti-tumor promoter from seaweed, the anti-tumor promoting activity of Ecklonia stolonifera, Undaria pinnatifida and Laminaria japonica extracts were determined by Epstein-Barr virus (EBV)-early antigen (EA) induction caused by a tumor promoter, teleocidin B-4. The methanol extracts of seaweed were subsequently fractionated with diethyl ether, distilled water, chloroform and ethyl acetate. Among the solvent fractions tested, chloroform and ethyl acetate fraction of E. stolonifera showed a high anti-tumor promoting activity at the levels of 88.0 and $85.9\%$ by the addition of 20 ${mu}g/m{ell}$, respectively. To characterize anti-tumor promoters from solvent fractions of E. stolonifera, the effects of phenols, chlorophyll derivatives and carotenoids on the anti-tumor promoting activity were investigated. Phenols, such as bromophenol and phloroglucinol showed anti-tumor promoting activity of $57~66\%$ at 20 ${mu}g/m{ell}$. Pigments, such as chlorophylls and carotenoids exerted high anti-tumor promoting activities. Chlorophyll a and pheophorbide a exhibited the activity of $77.4\%$ and $66.6\%$ at 5${mu}M/m{ell}$, respectively. The active compounds of carotenoids were tentatively identified as lutein and $alpha-cryptoxanthin$ from the profiles of visible spectra and R_f value of their authentic compounds, and showed anti-tumor promoting activities of $76.9\%$ and $84.4\%$ at dose of 20 ${mu}g/m{ell}$, respectively.