The purpose of this study was to investigate the properties according to population statistical properties, customary behavior in the Korean professional baseball and preferences of spectators through customer segmentation by RFM analysis of Korean professional baseball spectators. The conclusions of this study are as follows. Until now, the spectating style of the Korean professional baseball has consisted of very limited spectator base. It is impossible to consider that the Korean professional baseball has broad base compared with other competing viewing culture such as movie, museum, concert, ``play, Madang-guk (Korean traditional play) and musical`` and art museum. Nearly 60% of spectators are accompanied by their friends and boyfriend or girlfriend. It can be said that the Korean professional baseball spectators have mainly consisted of those in their twenties. The RFM scores were highly formed in males, old people, self-employed individuals, less than high school diploma and the culturally disadvantaged. In other words, it can be said that other classes watched according to the cycle watching by various spectators rather than intensive visits. There were differences in the RFM scores of stadiums and their favorite teams. The higher group was formed with a focus on the stadiums in capital area such as Jamsil, Munhak and Mokdong. On the other hand, the higher group was formed based on the stadiums in local areas such as Medeung in Gwangju, Daegu, Daejeon Hanbat and Sajik, in descending order. The favorite teams were shown LG Twins, Nexen Heroes, SK Wyverns, Doosan Bears, Samsung Lions, Lotte Giants, Hanwha Eagles and Kia Tigers, in descending order.