Najarian has four decades of experience in securities and futures markets. He co-founded trading options and securities education firm MarketRebellion.com, and contributes regularly to CNBC Business TV.
Najarian said: "EBet is an exciting company with a solid strategy, field-tested products in the wagering space and a management team that can drive the business into a new era.
"Their geographic reach, expansion plans and customer base, I believe, will help them carve out a leadership position within the industry. I am thrilled to be joining and contributing my experience to accelerate the growth of EBet, helping it realise its enormous potential."
He has previously traded on the Chicago Board Options Exchange and spent 25 years as a floor trader, during which time he has been a member of the NYSE, CME and CBOT.
Najarian co-founded online brokerage firm TradeMonster in 2005, before selling the company to E*TRADE Financial Corp for $750m in 2016.
Currently, Najarian works as an active investor and market analyst, and has delivered keynote addresses for the NYSE, Euromoney and Institutional Investor.
EBet CEO Aaron Speach said: "We are delighted to welcome Jon Najarian as an Advisor. His vast experience will undoubtedly provide EBet with strategic insight that will help shape the direction and further success of the company."
Last week, EBet undertook a range of drastic measures in an effort to boost profitability, with the company cutting its total number of employees and contractors by 54%.