Claeissens, also spelled Claessens or Claeissins is a Dutch language surname. It may refer to:
Antoon Claeissens (c.1536–1613), a Flemish painter Gillis Claeissens (1526–1605), a Flemish painter Pieter Claeissens the Elder (1500–1576), a Flemish painter Pieter Claeissens the Younger (c. 1535–1623), a Flemish painter