Aguero is a two-time victor of the Premier League and has netted at least 20 league goals in four of his six seasons.
Speaking as a pundit on Sky Sports, Henry said: 'The only one who is world class, or has been world class, is Aguero because of the longevity of what he has done in this league, year in and year out.
Alvaro Morata soared 22 places into the No 2 spot and nearly toppled Aguero atop the chart after hitting a hat-trick during Chelsea's 4-0 win at Stoke, breaking the deadlock within two minutes - set up by a long pass from Cesar Azpilicueta (No 5, up 13 places).
Manchester City's Sergio Aguero, Manchester United's Romelu Lukaku, Tottenham's Harry Kane and Chelsea's Alvaro Morata have all started strongly this season, with three of them already helping themselves to six goals and Kane notching four.
"He's won the league here and got to the final of the World Cup". He's been doing it the longest so you have to give him a bit of credit. "Probably Harry Kane. I think he is the only Englishman that has been voted in the FIFPro top players".
"The others, I have no doubt will be". Kane himself said he's not in that bracket yet because of the reasons I mentioned.
Kane is the holder of the Golden Boot now and won it the previous season as well, but the competition has heated up since the summer transfer market. It was short in the Europa League and the Euros.
Harry Kane of Tottenham Hotspur celebrates scoring his side's first goal during the Premier League match against West Ham United.
Aguero, 29, will join Eric Brook as City's all-time top scorer with 177 goals should he net against Shakhtar Donetsk in the Champions League tonight.
Overall Kane has 82 league goals in 122 outings at a record of 1.49 a game, which is slightly ahead of Aguero on 1.46.
To conclude the chat, Henry did state his belief that Kane, Lukaku and Morata will all become world class players in the future.