The Brazil international has scored three goals in six Premier League appearances in the 2016-17 campaign so far.
Firmino inspired Liverpool to come from a goal behind to secure a 2-1 comeback win against Swansea City in their most-recent outing.
Klopp came up against the former Hoffenheim forward during his spell in charge of Borussia Dortmund before he took over the reins at Anfield in 2015.
And the Liverpool boss has heaped praise on the South American playmaker ahead of the Merseyside club’s home clash against Manchester United on Monday night.
“The difference is not too big because I knew Roberto before I came here and he is a very good player,” Klopp told his pre-match media conference at Melwood training ground on Friday afternoon.
“I played [against him] a number of times when he was at Hoffenheim so I knew a lot about him.
“The only thing what he shows now is this mixture of talent and attitude. He’s a really good player and he loves what he is doing.”
Firmino moved to Liverpool in a £29m deal from Bundesliga side Hoffenheim under Klopp’s predecessor Brendan Rodgers.
The 25-year-old scored 11 times in 49 appearances in all competitions in his first season in the Premier League.
Liverpool are in fourth place in the Premier League and three points behind leaders Manchester City.
The Reds are three points ahead of their bitter rivals ahead of Monday night’s clash.
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