It was the first time that Aquino has held a double-digit lead in a Social Weather Stations (SWS) poll since December.
The poll, conducted on April 16-19 and published on Monday, showed that support for the son of the country's late democracy icon, Corazon "Cory" Aquino, edged up 1 point to 38 percent.
The country will hold national elections and launch its first automated vote count on May 10.
Support for Aquino's closest rival, property magnate-turned-senator Manuel "Manny" Villar dropped two points to 26 percent in April.
Villar's ratings have slipped since February, when he closed in on Aquino's lead with a two-point margin, partly due to allegations by his critics that President Gloria Macapagal Arroyo and her husband were supporting his candidacy.
Arroyo is unpopular due to several corruption scandals during her nine years in office.
The number of undecided also inched up to 6 percent from 5 percent, according to the survey of 2,400 registered voters.
Aquino's ratings have been steady at above 35 percent since the country's two main independent pollsters, SWS and Pulse Asia, started surveys on presidential candidates late last year.
Pulse Asia is likely to issue its latest poll later this week.
Former President Joseph "Erap" Estrada, ousted from office in 2001, and administration candidate Gilberto "Gibo" Teodoro remained at third and fourth respectively in the SWS poll.
Estrada's ratings dropped 2 points to 17 percent from the previous survey in March. Teodoro's support improved by 3 points to 9 percent on the strength of the administration party's wider reach, but it was not enough to lift him from single-digit levels.
The results of the opinion poll, which have a 2 percent margin of error, were posted on the Social Weather Stations website http://www.sws.org.ph/.
An informal poll conducted by Thomson Reuters during the annual convention of foreign exchange traders over the weekend showed 77 percent, or 37 out of 48 respondents, favored Aquino as president. Teodoro came in a far second with 10 percent while Villar came in third with 8 percent. No one voted for Estrada.
