Haaland has scored 15 of City's 33 Premier League goals, including three hat-tricks, and bagged another five in the Champions League in 12 appearances in all competitions.
"He is one of the best. I have many very, very good strikers and Erling is one of them," Guardiola told reporters on the eve of City's Champions League game at FC Copenhagen.
"He understands quickly and he is a nice guy. He is able to do this for the team, but we need to work together and that has happened. I speak a lot about him, but sometimes I should not have to because the numbers, they do this."
Haaland scored twice last week in City's comfortable 5-0 win over Copenhagen, who are bottom of Group G with one point, but Guardiola kept his cards close to his chest on plans for resting the Norway international.
City can seal their spot in the knockout stages with a win at the Parken Stadium on Tuesday, after taking a maximum nine points from their first three games.
"It's true there's a risk of fatigue... Tomorrow I will decide on the selection. I will speak with players, doctors and physios and decide," Guardiola said.
"We are not going to underestimate them (Copenhagen). It will be no exception. If it does not go well, it will not be because we do not play well but because Copenhagen play well.
"We want to get into the last 16 and this is what we will try to do... We have the opportunity to close qualification. In the last games we played very well. I'm more than satisfied so far."
Defenders John Stones (28) and Kyle Walker (32) plus midfielder Kalvin Phillips (26) were not part of City's 21-man squad that travelled to the Danish capital as they remain sidelined by injuries.
Follow all the action from the Champions League this week on Flashscore.
