The tech giant plans to fly 30 balloons over the island as part of its Project Loon, after thousands of phone towers were destroyed in the storm.
According to the US Federal Communications Commission (FCC), 83 per cent of phone towers are out of service, with communications companies scrambling to install temporary masts.
The FCC confirmed it had approved a filing from Alphabet Inc, Google's parent company, that said the company would work to "support licensed mobile carriers' restoration of limited communications capability" on the island.
The balloons, that travel on the edge of space, were designed to extend Internet connectivity to people in rural and remote areas worldwide but they have also been deployed for disaster relief efforts.
Google provided emergency phone service as part of Project Loon in Peru earlier in the year following widespread flooding.
It comes as FCC Chairman Ajit Pai announced he would form a Hurricane Recovery Task Force with an emphasis on addressing challenges facing Puerto Rico and the US Virgin Islands.
"It is critical that we adopt a coordinated and comprehensive approach to support the rebuilding of communications infrastructure and restoration of communications services," Mr Pai said in statement.
Millions of Puerto Ricans are still living in the dark after 140mph winds and torrential rain annihilated 80 per cent of the island’s electricity. Two weeks on, just nine per cent of residents have power, according to the latest government figures.
Google is not the only tech giant to offer aid to the island. Tesla Inc has also announced it would send more battery installers to help the relief efforts.
CEO Elon Musk said he believes he will be able to rebuild Puerto Rico’s power grid with batteries and solar power.
Mr Musk said he was diverting resources from a semi-truck project to fix Model 3 bottlenecks and "increase battery production for Puerto Rico & other affected areas."
Separately, Puerto Rico Governor Ricardo Rossello wrote on Twitter he had a "great initial conversation with @elonmusk tonight. Teams are now talking; exploring opportunities. Next steps soon to follow."
Additional reporting by Reuters