Do you think is Bob Marley the best music artist in the 20th century ?  

Bob Dylan.
Bob Marley was great, no doubt about that.
Lennon was great as well
So was Frank Sinatra
The list of truly great music artists is huge and there are even some people who would say that the now dead King of Pop Michael Jackson was the greatest,
So I reckon its not a question with a definitive answer.
I heard a funny joke about MJ
How did he die?
Sat too close to the fire and melted!!!

Bob Marley would be up there, but the top 10 would include, I think, Elvis, John Lennon, Paul McCartney, Sinatra, Ella Fitzgerald. Other contenders...Hendrix, Jagger, Bowie, Michael Jackson.

Yes, no doubt, Bob Marley the best music artist in the 20th century. He was a Jamaican singer-songwriter and musician. Marley's best known hits include "I Shot the Sheriff", "No Woman, No Cry", "Could You Be Loved", "Stir It Up", "Jamming", "Redemption Song", "One Love" and, together with The Wailers, "Three Little Birds", as well as the posthumous releases "Buffalo Soldier" and "Iron Lion Zion" and many more. He was born on February 6, 1945. He died at Cedars of Lebanon Hospital in Miami on the morning of May 11, 1981, at the age of 36.

defnetly.
he is d great artist wen compared wid d tym.
his songs hav some sort of experiment.......observe it.
so i vote him he is great artist