The purpose of this study was to categorize official twitter messages and find out each team's marketing strategy by using Ruby program. For the analysis 3 thousands official twitter massages were used for each 4 major probaseball teams, Samsung Lions, KIA Tigers, SK Wyverns, and NC Dinos. The results were as follows. Firstly, The marketing messages of pro baseball teams were different than typical companies. Pro baseball's official twitter marketing massages can be grouped into 5 category, Team Awareness, CSR, Customer Service, Engagement and Promotion. Secondly, Twitter marketing message strategy was differentiated by each pro baseball team. NC Dinos using twitter to increase team awareness while Samsung Lions deliver their premium team image as a KBO league champion and highlight marketing events with star players. KIA Tigers has shown most passive activities on twitter. Most of messages were just informing game and schedule. SK Wyverns actively using twitter they were answering questions from fans and very engaged to use twitter as a marketing tool.
