The relatives, who have complained bitterly about the investigation and called for officials to be prosecuted in connection with the attack, flew to Moscow and met Putin on Friday on the second day of a mourning period on the anniversary of the three-day ordeal.
The Beslan Mothers' Committee had long demanded a meeting with the president to air its members' protest over the government's handling of the tragedy, both the botched rescue operation and the subsequent investigation, which they mistrust.
"I must say immediately, I agree with those who believe that the state is not in condition to provide for the security of its citizens to the necessary degree," Putin said in televised comments at the beginning of the meeting.
But he said that was "no excuse for officials' improper fulfilment of their duties".
No full protection
Still, seemingly seeking to deflect the blame grieving relatives have trained on the state, Putin stressed that no government can fully protect its people against terrorism.
He referred to bombings in Spain and Britain and to the 11 September attacks, saying US law-enforcement agencies "slipped up and allowed this horrible terrorist act".
Putin said no state can fully
protect citizens from terrorism
Putin was shown in close-up in most of the footage on state-run Rossiya television, and the immediate reaction of the relatives was unclear.
Putin tried to assure the group that in spite of their apparent suspicion to the contrary, he had been kept fully apprised of their grievances.
"Your feelings are understood by any mother, any father, any normal person," he said. "I know it all, I have been briefed about the problems and worries that concern you."
Eight women held an all-night vigil on Thursday night - the first night of the three-day mourning - in the gutted gymnasium where rebels had herded more than 1100 hostages on the first day of school last year.
More than 330 victims died, most in the firestorm of explosions and gunfire that brought the crisis to a bloody end two days later. Another group spent the night in the cemetery, where the rows of graves tell of Beslan's loss.