According to Official Guinness Records,
The most people maypole dancing is 388 and was achieved by the Cultural Council of Schwäbischen Albvereins (Germany) in Ulm, Germany, on 28 April 2013. Kulturrat des Schwäbischen Albvereins is an organisation of 110,000 members supporting homeland traditions, hiking and environmental issues in South-Western Germany. Founded in 1888, 2013 marks its 125th year anniversary. The record attempt formed part of the jubilee celebrations of the Schwäbischer Albverein. Participants danced around 8 separate maypoles for 10 min 29 secs.
For a complete list of 2013 records, please visit 2013 Guinness Records in Germany.