Michael Salmon, 30, used his position as freelance producer of a show, "Cosy", at Cardiff's Millennium Centre, to obtain grants.
Some grants came from the Arts Council of Wales and Arts Unlimited, set up to fund projects with disabled performers.
Salmon, from Grangetown, Cardiff, admitted five counts of fraud.
The court heard that he used £9,000 to fund his own lifestyle, mainly on trips to London.
But most of the money he defrauded was lost by his own mismanagement of several theatrical projects.
One grant of £30,000 was obtained by falsifying a bank statement.
The deception took place between May 2015 and February 2016.
Jailing Salmon, Judge Paul Lewis QC said he had lied to theatrical directors who had gone to him for help in raising grants for their productions.
He said: "This was public money intended for good causes which never reached them.
"There was substantial financial mismanagement with money being transferred from one project to another when it shouldn't have been."

Northampton Town's League One 3-0 home win over Coventry City was disrupted several times by fans on Saturday.
Northamptonshire Police said six arrests were made when spectators from the away stand invaded the pitch and a further three when flares were let-off.
Coventry City said the disruption was "unacceptable". Northampton declined to comment. Those arrested were bailed.
Northampton Town said it would not comment until a decision was made by the Football Association or English Football League on an investigation.
"The repeated disruptions to yesterday's match at Northampton Town were unacceptable," a Coventry City spokesman said.
"Coventry City FC will support all subsequent investigations by the police and football authorities."
Match reports said the fans were protesting against the Coventry club's owners.
Supt Chris Hillery said: "During the fixture we were made aware that some of the spectators in the away South Stand had planned a mass pitch incursion at a designated time.
"As a result, match officials turned off the scoreboard time display and officers were placed in front of the West Stand and in the players' tunnel to prevent people intent on disorder entering these areas en masse."
There was no serious disorder, violence or injury, police said.

The Scottish Seabird Centre wants to expand its education and conservation programmes to include all marine life in a bid to remain viable.
A National Marine Centre for Scotland is designed to be built at the existing Seabird centre in North Berwick.
An interactive experience is planned to inspire people to care for the natural environment above and below the waves.
The Scottish Seabird Centre said it needs to evolve to remain viable, it has more education requests than it can cope with and visitor expectations are at an all-time high.
It has secured £3.3m Heritage Lottery funding but needs another £2m if its vision is to become a reality with the centre planned to open in 2020 for Visit Scotland's year of coasts and waters.
Grace Martin, project director for the National Marine Centre, said: "The Scottish Seabird Centre currently offers visitors an opportunity to engage with nature in a sustainable way.
"As a conservation and education charity, we welcome 4,000 schoolchildren a year and lead projects such as SOS Puffin.
"But, as with all charities, we must move with the times to remain viable and to achieve our objectives of inspiring people to care for wildlife and the natural environment.
"We have more education requests that we can accommodate and visitor expectations are at an all-time-high.
"Our vision is to create a centre that is of national significance and one that the local community is proud of."
Professor John Baxter, principal advisor at Scottish Natural Heritage and a trustee of the Seabird Centre, said: "The marine environment of Scotland supports a fantastic array of habitats and wildlife.
"Under the surface of the seas is a hidden and very special world that we want to reveal and bring to life, for people of all ages, in exciting and engaging ways.
"Scottish universities are at the cutting-edge of marine environment research but there are at present limited opportunities for the public to share in this work.
"Through public engagement we know there is a high level of interest in our seas, coasts and wildlife.
"This new attraction will provide an immersive and interactive experience, communicating the latest research and inspiring people to look after our natural world. It is vital that we protect and conserve our seas and their wildlife for future generations."
An independent theatre producer who fraudulently claimed £65,000 in grants has been jailed for 18 months at Cardiff Crown Court.
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Nine men have been arrested over a pitch invasion and flares being thrown at a football match.
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Plans for a £5.5m National Marine Centre for Scotland have been unveiled in East Lothian.