Bosses at the Yorkshire Wildlife Park believe the venue could become the biggest zoo in England.
Plans have been drawn up to extend the site, in Branton, in the next few years, with a new entrance more shops, and a hotel on the site of the attraction.
Officials have told business leaders in Doncaster they believe the boost of the new access from the Finningley and Rossington Relief Road Scheme link road and the airport could bring major increases in visitor numbers.
Chief executive John Minion told the Doncaster Place Board ambassadors that since the park opened in 2008, its visitor number had grown from 60,000 to 760,000 a year, and this year they were hoping for 800,000.
Speaking at a meeting at the park, in Branton, he said: "With the plans we have, we could be looking at 1.5 million coming through the gate. That would put us as number two zoo in the country behind Chester, which gets about 1.8 milllion.
"We could become the biggest zoo in the UK - it's incredibly exciting for Doncaster."
Mr Minion believes the planned new entrance off the airport link road should help cope with traffic issues that had affected the park on occasions in the past on its busiest days.
Director Cheryl Williams said: We have had the potential to become a leading, if not the leading attraction in the UK. and that would be immense for area in terms of destination.
"One of the key issues is connectivity. Within an hour and a half's drive time, there are 20 million people. "
She said the Doncaster area had potential national and international appeal, with the racecourse and plans for a PGA standard golf course at Rossington Hall, which had the potention to bring in hundreds of thousands of golf fans.
The planned expansion at the wildlife park is expected to double its workforce, and Ms Williams said she was keen to employ local people in areas ranging from animal care to catering.
She said: "We want to work with the colleges so that in two years time when we're recruiting we can get our workers here in Doncaster."
She added they were looking at talking with Doncaster Sheffield Airport about possible weekend deals. She said in Germany and the Netherlands zoos were very popular attractions and zoos there could get 3 million visitors a year and the park would like to tap into that market.
Mr Minion and Mrs Williams were addressing the Doncaster Ambassadors scheme, which shares information about developments in the borough with businesses, who they then want to share the information with clients from around the country.
Doncaster Chamber is currently encouraging firms to sign up for its ambassadors scheme as part of the Doncaster Place Board, which is an organisation set up by businesses to market and promote the borough.