Paul Ramsamy, 46, claims the pair confronted him after apparently mistaking him for an armyman because he was wearing combat trousers and boots.
The father of two said Michael Adebowale, 22, and Michael Adebolajo, 28 - who were shot by police soon after the attack in Woolwich and are now under arrest at separate hospitals in London - had followed him in the street in Greenwich as he walked home.
"They looked at my camouflage trousers and boots. I then thought they just wanted me to buzz them into the flat block but that was obviously not the case. When I saw what happened in Woolwich, I recognised them and realised how lucky I have been. They must have been hunting for soldiers to attack when they followed me," he said.
"I realise now what a lucky escape I had. They were obviously looking for a soldier to attack in the time before they struck. They were whispering to each other when they walked away, it was very scary. They obviously saw I was not a soldier and let me go. They could have followed me into the lift and attacked me. I feel lucky to be alive," Ramasamy added.
More From This Section
Drummer Lee Rigby, who had served in Afghanistan and was attached to the Regimental Recruiting Team, died after he was hacked to death by the two attackers.
The pair are thought to have planned the attack in Adebowale's flat in Greenwich, which was raided by up to 20 heavily armed police yesterday.
Neighbours said both men were regularly seen at the address where Adebowale was living with his mother Juliet.
A man and a woman, both 29, were arrested on suspicion of conspiracy to murder during a series of raids on six addresses in London, Essex and Lincolnshire yesterday.