"We're basically taking these animals from the wild to die in a show for our entertainment," said Nancy Gibson, head of the Love Wildlife Foundation
The groups said they would petition the fisheries department against granting the dolphinarium an aquatic zoo licence for the island resort.
"People won't come to Phuket for a dolphin show," said Nancy, denying the claim that the dolphinarium would promote tourism.
In depth: From dolphins to tigers, Thailand's animal shows taking their toll
In recent months, wildlife groups including SEEK Phuket (Society, Environment, Economy & Knowledge), the Love Wildlife Foundation and DolphinProject.org have hosted several events including a speech by Richard O'Barry, the host of the 2009 documentary The Cove.
An official at the company that owns the land - said by activists to be behind the development - declined to comment on the protests. He also refused to confirm or deny that the facility would house dolphins.
A Ukrainian dolphinarium company, linked to the Phuket attraction according to activists, is taking bookings for shows in Phuket from October.
The Phuket venture is not Thailand's first. Pattaya Dolphin World has been giving tourists in the Thai resort town the chance to swim with dolphins, and outraging animal welfare activists, since it opened in 2011.
That dolphinarium displays two Irrawaddy dolphins and a Indo-Pacific humpback. The Indo-Pacific humpback is listed as near-threatened by the International Union for Conservation of Nature. The Irrawaddy dolphins are listed as critically endangered, and their commercial trade is forbidden.