The increasing population leads to higher passenger travel demand in Stockholm. The public transport becomes more and more crowded in rush hours. However, passengers carry out decisions usually based on limited traffic information and their travel experience. Passengers cannot take the initiative to avoid crowding based on existing SL traffic information. Real time crowding information (RTCI) research aims to help passenger to have more initiative to plan their travel in metro system, and assist operator to have higher space utilization efficiency. RTCI system contains4 subsystems: projection system, communication system, speaker system and recording system. The practical test was applied in Tekniska Högskolan metro station for two weeks in May 2015 with the permission from SL. The triangle analysis was applied to analyze the impacts of RTCI. The analysiscontains three analysis methods: passenger load data analysis, video record analysis and interview result analysis. The interview result shows RTCI increased round nine tenth of passengers ‘satisfaction and 43% of interviewees thought it was very useful for them. The calculation based on video record and interview result shows that 25% of passengers consulted this information and changed their behaviors on platform. According to the video record, the path became wider and passenger flow became smoother while RTCI system was activated. Passenger distribution was more even in metro based on passenger load data. The number of passengers who got into last unit train increased 8%, and the number in first and second unit train decreased 4% during RTCI practical test. The thesis mainly focused to analyze the impacts of RTCI instead of solving technical challenges. But the technical solution for RTCI system was proposed in thesis. The concept - “Smart Travel” was discussed in chapter11 which mainly considers travel time, crowding information and travel cost as most important factors to passenger.