On Thursday, Mohammad Cholily, 28, smiled and gave the thumbs-up after getting the sentence, which was three years longer than had been recommended by prosecutors.
"In the eyes of Allah there is no guilty person," he said.
Cholily's verdict came just hours after another militant, 33-year-old Dwi Widyarto, was handed eight years for his role in the bombings, which killed 20 bystanders, in another court.
In a separate hearing in another court in Denpasar, the Balinese capital, Widyarto got eight years after being found guilty of helping transfer a recording of Noordin threatening Western nations.
"It is too long, far too long," Widyarto said of his sentence as he was escorted from the courtroom. But the court judge said he was "convincingly guilty of having taken part in terrorism".
The October 2005 attacks were a huge blow to the mostly Hindu resort of Bali, which was already struggling to recover from bombings three years before that left 202 people dead.
Cholily learned his deadly craft from the late master Malaysian bomb-maker Azahari Husin, and judge Gusti Ngurah Astawa said the accused was a "dangerous" man who deserved a stiff prison sentence.
"The crime of this defendant increased fear, particularly in Bali and generally across Indonesia," he said. "It ruined tourism in Bali and Indonesia. It was an extraordinary crime - and a crime against humanity."
Dwi Widiyarto got eight years for
his role in the 2005 bombings
But the judge said he had refrained from handing down an even longer prison term for Cholily, who was found guilty of supplying the equipment used in the attacks, because the bomb-maker had admitted his crime.
Cholily was arrested last year with a backpack bomb that he was believed to be delivering to militants from the group of Noordin Mohammad Top, who along with the late Azahari was considered to be the mastermind of the 2005 attacks.
His lawyer Mujito Rahman denied that parts Cholily was found to have had been used in the bombings.
The verdicts came just two days after another man, Abdul Aziz, was given 10 years for his role in the 2005 bombings. A verdict is still awaited over another suspect.
Attacks in Indonesia have been blamed on the al-Qaeda-linked Jemaah Islamiyah (JI) network, though some militants - including Azahari and Noordin - were believed to have split and formed an even more hardline group.
Azahari was killed in a police raid on his hideout in East Java last November but Noordin remains on the run. He has narrowly escaped police several times.
Three other men - Amrozi, Ali Ghufron alias Mukhlas and Imam Samudra - had been scheduled for execution last month for their roles in the 2002 attacks, which were also linked to JI. The killings were delayed to a final appeal.