LaCasse or Lacasse (French pronunciation: [lakas]) is a French surname. Notable people with the surname include:
Lou-Adriane Cassidy-Lacasse (born 1997), Canadian singer-songwriter Alex Lacasse, Canadian pop artist Cloé Lacasse (born 1993), Canadian soccer player Florent Lacasse (born 1981), French middle distance runner Geneviève Lacasse (born 1989), Canadian ice hockey player Josée Lacasse (born 1965), Canadian alpine skier Josée Lacasse (born 1970), Canadian rugby union player Joseph Lacasse (1894–1975), Belgian artist Joseph-Henri-Gustave Lacasse (1890–1953), Canadian journalist, physician and politician Marie-Ève Lacasse (born 1982), French writer Raphaëlle Lacasse (born 2000), Canadian tennis player Ryan LaCasse (born 1983), American football player Suzanne Lacasse (born 1948), Canadian civil engineer Emerance Maschmeyer-Lacasse (born 1994), Canadian ice hockey player