Ivan is a Russian cosmonaut who completed 679 orbits around the Earth with Igor, another cosmonaut in the Russian space program. In his ascent to Earth, he and Igor come down into the lagoon of Gilligan's Island where he is met by the Professor and the castaways. He's a bit more level-headed than Igor who turns out too quick to volunteer information to the castaways, but like Igor, he is not ready to believe their stories of being shipwrecked, forbidding them entry to their spacecraft. He's also a trained electrical engineer who gets the Professor's help to fix their radio after Gilligan shorts it out, and he conspires with Igor to leave the castaways behind by getting them drunk on Vodka, but he's the first to pass out as Igor parties past midnight, not realizing that the others have been drinking water. The Castaways leave them to be found by their retrieval team, but by time, they get back the next morning, Igor and Ivan have been picked up, and the castaways have been abandoned once again.
- Ivan was played by actor Danny Klega.
- Ivan is one of two characters named "Ivan" in the series; the others being Ivan from Rescue from Gilligan's Island.