Kaio Márcio de Almeida (born October 19, 1984 in João Pessoa, Paraíba, Brazil) is a Brazilian swimmer, who specializes in butterfly. He is also known as: Kaio Márcio, Kaio Márcio de Almeida, Kaio Almeida, or Kaio de Almeida.
In December 2005 he set a World Record in the short-course 50m butterfly at 22.60. His swim bettered the existing record of 22.71 of the USA's Ian Crocker from October 2004 and would stand for almost three years until Matt Jaukovic from Australia improved the record to 22.50 in October 2008.
He was a member of the Brazil's Olympic team in 2004 (Athens) and in 2008 (Beijing). In Athens, he finished 17th in the 100 m butterfly and 19th in the 200 m butterfly. In Beijing, he finished 15th in the 100 fly, and 7th in the 200 fly.
De Almeida finished 4th place in the 200 m butterfly at Rome 2009. In November 2009 he set a World Record in the short-course 200m butterfly at 1:49.11.