Assuming you're talking about the British Royal Family, there are two categories of "royal princesses" - those who are married to princes and those who are princesses by birth.

The princesses by blood, and their husbands are:

• Princess Beatrice is unmarried.
• Princess Eugenie is unmarried.
• The Princess Royal (Anne) is married to Vice-Admiral Sir Tim Laurence, her second husband; her first was Captain Mark Phillips - they divorced.
• Princess Alexandra is widowed. Her husband was the Hon Sir Angus Ogilvy.

The princesses by marriage, and their husbands are:

• The Duchess of Cornwall (Camilla) is the wife of the Prince of Wales (Charles). He was divorced from Lady Diana Spencer.
• The Duchess of Cambridge (Catherine/Kate) is the wife of the Duke of Cambridge (William).
• Princes George and Harry aren't married.
• The Duke of York (Andrew) is divorced from Sarah, Duchess of York (she is, therefore, no longer a princess.)
• The Countess of Wessex (Sophie) is married to the Earl of Wessex (Edward).
• The Duchess of Gloucester (Birgitte) is married to the Duke of Gloucester (Richard).
• The Duchess of Kent (Katharine) is married to the Duke of Kent (Edward).
• Princess Michael is married to Prince Michael. Her own name is Marie Christine.