Percy Jackson & the Olympians is Rick Riordan adventure and fantasy book series based on Greek Mythology. There are five books namely The Lightning Thief, The Sea of Monsters, The Titan's Curse, The Battle of the Labyrinth and The Last Olympian. Additional other extension books entitled The Demigod Files and Demigods and Monsters were also created.

The main character is Percy Jackson who finds out that he is the son of Poseidon, the Greek god of the sea and earthquakes. He knew that legendary beings of ancient Greek time are still existing such as monsters, cyclopes, empousai, Titans, and also the Olympians (Greek gods). He is always attacked by monsters because he is a child of one of the "Big Three" (Zeus, Poseidon, and Hades). Percy meets many other young demigods, both friendly and dangerous, who are also in the process of discovering their heritage and powers.

The Percy Jackson & the Olympians series stayed on the New York Best Seller list for children's books for 129 weeks as of January 6, 2010.