The purpose of this study was to first identify the relationshi p of professional baseball team`s CSR activities and spectators` team attachment and then to identify the mediating effect of fit. The study consisted of dis-tributing a survey(construct reliability .719~.939) to 344 spectators from the 2010 CJ Magu Magu Professional Baseball League`s 3 home teams and 3 away teams using the convenience sampling method. As a result, data from 294(85.5%) participants were analyzed after recollection and screening for reliability. The data analysis consisted of applying descriptive analysis, CFA, and SEM using SPSS 18.0, Amos 18.0 and of using bootstrapping to identify any indirect effect. The results are as follows: First, team`s donation and amateur athlete support positively and significantly affect Team-CSR fit. Second, amateur athlete support positively and significantly affect team attachment. Third, donations have an indirect effect on team attachment through the complete mediating effect of Team-CSR Fit. Forth, in the relationship between amateur athlete support and team attachment, Team-CSR fit partially has a mediating effect.