I-naphthylamine　is　a　probe　with　intra-molecular　charge　transfer　in　nature.　Its　characteristic　band　(lambda)　is　sensitive　to　the　polarity　of　environment.　It　was　found　that　the　semilogarithmic　plot　of　lambda　versus　surfactant　concentration　(c)　exhibited　two　inflection　points.　The　first　inflection　point　corresponded　to　the　critical　micelle　concentration　(c(mc)),　and　the　second　inflection　point　(c(m))　addressed　the　critical　point　reaching　dense　structure　in　the　micellar　core.　The　results　showed　that　Gemini　surfactant　only　forms　small　aggregates　at　the　cmc.　Over　the　range　from　cmc　to　c(cm),　the　aggregation　number　of　the　micelle　rapidly　increases　with　increasing　c.