37 employers including eBay, IBM, Siemens, Yahoo and Bank of America are taking part in the event at the RDS.
Organisers of the fair Monster.ie say the number of jobs available is a sign that unemployment is starting to ease and companies are beginning to hire.
The event will continue until 4pm today.
The most recent jobless figures here showed the number of people signing on for unemployment benefit fell slightly in October, from 12.6% in September to 12.5%.
The headline figure dropped by 7,447 to 412,407, although it is still almost 65% ahead of the same month last year.
