The King of Comedy is Scorsese's best film.
1. Mean Streets
2. Taxi Driver
3. The King of Comedy
Alternate ranking
1. Goodfellas
2. Taxi Driver
3. Raging Bull
4. The Departed
5. Bringing Out The Dead
6. The Age of Innocence
7. Alice Doesn't Live Here Anymore
8. Mean Streets
9. The Aviator
10. The King of Comedy
11. The Last Waltz
12. Gangs of New York
13. Cape Fear
14. Casino
After Gangs, they stop being good. I haven't seen a lot of his more interesting films though such as
After Hours,
The Last Temptation of Christ,
A Personal Journey,
My Voyage to Italy, or
No Direction Home. Regardless of what he's making, Scorsese's films are always worth watching