The title Earl of Dorset has been created at least four times in the Peerage of England. It was created in 1411 for Thomas Beaufort, who was later created Duke of Exeter. The peerages became extinct on his death.

It was next created in 1441 for Edmund Beaufort who was later created first Marquess of Dorset (1442) then Duke of Somerset (1446). These titles were forfeited by the second duke in 1464.

The last creation was in 1604 for Thomas Sackville, 1st Baron Buckhurst. In 1720 the seventh earl was created Duke of Dorset in the Peerage of Great Britain. On the death of the fifth duke in 1843 the peerages became extinct.

Earls of Dorset, first creation (1070)

• Osmund, Count of Seez (d. 1099) (extinct on his death)

Earls of Dorset, second creation (1411)

• see Duke of Exeter, second creation

Earls of Dorset, third creation (1441)

• see Marquess of Dorset, second creation

Earls of Dorset, fourth creation (1604)

• Thomas Sackville, 1st Earl of Dorset (1527-1608)
• Robert Sackville, 2nd Earl of Dorset (1561-1609)
• Richard Sackville, 3rd Earl of Dorset (1589-1624)
• Edward Sackville, 4th Earl of Dorset (1590-1652)
• Richard Sackville, 5th Earl of Dorset (1622-1677)
• Charles Sackville, 6th Earl of Dorset (1638-1706)
• Lionel Cranfield Sackville, 7th Earl of Dorset (1688-1765) (created Duke of Dorset in 1720)

Dukes of Dorset (1720)

• Lionel Cranfield Sackville, 1st Duke of Dorset (1688-1765)
• Charles Sackville, 2nd Duke of Dorset (1711-1769)
• John Frederick Sackville, 3rd Duke of Dorset (1745-1799)
• George John Frederick Sackville, 4th Duke of Dorset (1793-1815)
• Charles Sackville-Germaine, 5th Duke of Dorset (1767-1843) (extinct 1843)