The Scottish Land Fund grant is one of 10 across Scotland in the latest £1.6m allocation of money.
The Rousay, Egilsay and Wyre Development Trust (REWDT) said the funding would allow it to employ a project officer and ranger.
REWDT chairman John Garson said they hoped in the longer term to promote tourism on the island which has only 216 residents.
He added: “The project will help promote Rousay as an attractive place to live and provide two employment opportunities.
“The follow-on stages of this project will also have significant environmental advantages, will encourage and make it easier for locals and tourists to visit the area, provide well-needed additional public toilets and have the possibility of aiding digital connectivity across our islands. We can’t wait to get started.”
The other projects to receive funding are:
£229,000 to acquire a schoolhouse in Glenfarg, Perthshire, to create meeting rooms and a cafe
£54,000 to buy 21 acres of woodland in Lochmaben, near Dumfries
£38,000 to purchase land for parking, cycle space and an electric vehicle charge point at Hoswick visitor centre, Shetland
£178,000 to acquire the Kenmuir Arms Hotel in New Luce, Dumfries, and Galloway, to create a new community space
£187,000 to buy a four-bedroom house on Papa Westray, Orkney, to turn it into an affordable rented family home
£324,000 to purchase the category B listed Anderston Kelvingrove Parish Church in Glasgow, for use by community groups
£147,600 to buy a former harbour master’s house in Westray, Orkney, to turn into rented accommodation
£130,000 to buy a former Royal Bank of Scotland branch in Wigtown, for affordable homes and a visitor bunkhouse
£99,200 to take over ownership of the Tarves community hub in Aberdeenshire