Fernando Santos's team needed all the points to stay in charge of their own destiny in Group F, but the Iberian nation missed a whole host of chances as they were held to a stalemate in the French capital.
Austria had a golden chance to make the breakthrough inside three minutes when Marcel Sabitzer raced down the right and delivered a cross onto the head of Martin Harnik, but the number 11 somehow headed wide of the post.
An end-to-end opening then produced a headed chance for Portugal as Nani made contact on a loose clearance from Martin Hinteregger, but the attacker's effort did not trouble Robert Almer in the Austria goal.
In the 13th minute, Austria goalkeeper Almer was called into action on two separate occasions as the 32-year-old kept out a close-range effort from Nani, before tipping a Vieirinha strike wide of the post.
A horrible mix-up in the Austrian defence almost presented Portugal with another chance in the 19th minute when Almer's swing of the boot hit his own teammate Hinteregger, but the ball dropped wide of the post for a corner kick.
Three minutes later, Portugal had a brilliant chance to take the lead when Raphael Guerreiro picked out Ronaldo with a low cross, but the record-breaker placed his effort wide of the post.
Portugal continued to dominate and had another excellent opportunity in the 29th minute when Nani met a near-post corner, but his header hit the post and Joao Moutinho could only fire the rebound over the crossbar.
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Ronaldo had another chance 10 minutes before the break when he met a header from Ricardo Quaresma inside the Austrian box, but the Real Madrid forward could not find a route past Almer.
Austria had an opportunity of their own in the 41st minute when Pepe felled David Alaba just outside the box and the Bayern Munich left-back looked to pick out the far corner with the resulting set piece, but Vieirinha produced a goal-line clearance.
Ronaldo had two excellent chances to send Portugal ahead in the 56th minute, but the attacker was denied by a fine save from Almer, before the Austrian goalkeeper kept out the same player from the resulting corner.
Portugal continued to utterly dominate proceedings in the French capital and Ronaldo had another opportunity from a free kick in the 65th minute, but his effort was just over the crossbar as it remained 0-0.
Austria appeared to have settled for a point as the match headed for its final 15 minutes, but the pressure from Portugal was relentless and Joao Mario's introduction from the bench brought a sharpness to their attack.
Portugal had a golden chance to take the lead in the 78th minute when Ronaldo was pulled to the ground by Hinteregger inside the Austrian box, but the 31-year-old sent his spot kick against the post and Andre Gomes put the rebound over the crossbar as Austria somehow survived with their clean sheet intact.
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Ronaldo did have the ball in the back of the net five minutes from time, but the flag was raised for offside as his pain continued on what was a hugely frustrating night for Santos's team.
The result has left Portugal in third position in Group F ahead of their final match against Hungary next Wednesday. Austria, meanwhile, remain bottom and will need to beat Iceland next week to stand a chance of making the next round.