The Brazil international has scored twice and set up two more in his first three games of the season and was named the Premier League's Player of the Month on Friday, finishing ahead of teammate Cole Palmer, who had been Chelsea's previous winner of the award back in September 2024.
Asked whether Joao Pedro belonged in the same conversation as Haaland, who claimed last season's Golden Boot with 27 goals, Alonso did not hesitate.
"I would say yes," the Chelsea head coach said. "If you count how many top strikers we have in the Premier League, I'm sure that Joao is there, Haaland for sure is there.
"So I would rate him that way."
Since joining last summer, Joao Pedro has scored 25 times and provided 11 assists in 57 appearances, becoming the first Chelsea striker since Diego Costa to reach 20 league goals in a single debut season. Haaland, by comparison, has scored 42 goals and set up nine more in his last 57 matches for Manchester City. Joao Pedro signed a new contract at Stamford Bridge last month running until 2034 and was given the number nine shirt at the start of this campaign.
Alonso, who made 195 appearances alongside Karim Benzema during his own playing career at Real Madrid, drew a separate comparison between the Frenchman and his current forward, highlighting the more varied skill set Joao Pedro brings compared to the specialist finishing of Haaland, having played as a midfielder, number 10 and winger at different stages of his career.
"In many things he reminds me of Benzema, because he is good in the box, he is good out of the box, he is good coming to his left side, he is good with the head, he is very complete, he is intelligent," Alonso said.
"So yes, he is still young, still things to develop, but many, many absolutely outstanding qualities that he has."
Benzema, now 38 and a free agent, scored 523 goals in 994 appearances across his career at Lyon, Real Madrid, Al-Ittihad and Al-Hilal, along with his time with France, and won the Ballon d'Or in 2022.
Joao Pedro was a surprise omission from Brazil's World Cup squad this summer under Carlo Ancelotti, who coached Alonso during his time at Real Madrid, but has since been recalled for this month's fixtures against New Zealand and India. Asked whether that snub had provided extra motivation, Alonso played down the suggestion.
"He had enough motivation. He already had enough within him, so I didn't need to go there. It was painful for him, but that is in the past. We are now focused on what he is doing well and what he can do better," Alonso said.
"He has been outstanding. Not just in football terms, but in his personality, his maturity and his desire. He has a very clear goal this season, which is to have a great campaign and score a lot of goals."