After three days of deliberations, the chief juror on Thursday gave the courtroom the jury's first answers to 243 questions on the role of Dutroux and three co-defendants in a series of crimes that shocked Belgium nearly eight years ago.
Reading out the answers, the chief juror said Dutroux was also found guilty of murdering one of the girls.
The verdict is the climax to a trial that gripped Belgians for more than three months with details of a dungeon, suspected police complicity, and suggested links to a Satanic cult.
"Finally we will be able to punish these assassins," Jeanine Lejeune, grandmother of one of the victims, told local television as she entered the courthouse before the verdict was read. "This is the day that we will avenge my little girl."
Dutroux, his ex-wife Michelle Martin, and two other suspects were absent from the courtroom in this eastern Belgian town near the border with Luxembourg.
They will hear the long-awaited verdict once the chief juror has read the answers to all the questions and the judge has worked out any inconsistencies that may have arisen.
"Finally we will be able to punish these assassins"
The key questions that had yet to be answered with a simple "yes" or "no" concerned Dutroux's responsibility for the deaths.
The two youngest victims, both aged eight, starved to death in a dungeon built in the basement of his house near the southern city of Charleroi where he kept his victims locked up.
Dutroux admits kidnapping and raping some of the girls but denies killing them, blaming other defendants for the deaths.
If found guilty on all counts, Dutroux faces life in prison. The co-defendants could each get more than 20 years.
Sentencing will come after the prosecutor, defence lawyers and the suspects have had a chance to react to the verdict.