In William Shakespeare's play Hamlet, Gertrude is Hamlet's mother and Queen of Denmark. Her relationship with Hamlet is somewhat turbulent, since he resents her marrying her husband's brother Claudius after he murdered the king (young Hamlet's father, King Hamlet). Gertrude reveals no guilt in her marriage with Claudius after the recent murder of her husband, and Hamlet begins to show signs of jealousy towards Claudius. According to Hamlet, she scarcely mourned her husband's death before marrying Claudius.

Her name may derive from Gertrude of Bavaria, who was Queen of Denmark in the late 12th century.