Is the demigod files 6th book of series Percy Jackson and Olympians?

No, the Demigod Files is not the sixth book of the Percy Jackson & the Olympians series.

The Demigod Files is a collection of short stories and novellas set in the Percy Jackson universe, but it's not part of the main series.

Here's the order of the Percy Jackson & the Olympians books:

1. The Lightning Thief

2. The Sea of Monsters

3. The Titan's Curse

4. The Battle of the Labyrinth

5. The Last Olympian

Let me know if you have any other questions about the Percy Jackson series!