Mark Spencer may refer to:

• Mark Spencer (botanist), British forensic botanist
• Mark Spencer (computer engineer) (born 1977), American computer engineer
• Mark Spencer (guitarist) (born 1957), American guitarist
• Mark Spencer (British politician) (born 1970), British Member of Parliament for Sherwood
• Mark Spencer (New York politician) (1787–1859), New York politician
• Mark G. Spencer (born 1967), Canadian historian

• Marks & Spencer, a major British retailer
• Spencer (surname)