The 1965 creature feature Frankenstein Meets the Space Monster is also known as Duel of the Space Monsters, Frankenstein Meets the Space Men, Mars Attacks Puerto Rico, Mars Invades Puerto Rico, and Operation San Juan. From Wikipedia:
All of the women on the planet Mars have died in an atomic war, except for Martian Princess Marcuzan (Marilyn Hanold). Marcuzan and her right-hand man, Dr. Nadir (Lou Cutell), decide they will travel to Earth and steal all of the women on the planet in order to continue the Martian race. The Martians shoot down a space capsule manned by the android astronaut Colonel Frank Saunders (Robert Reilly), causing it to crash in Puerto Rico. Frank's electronic brain and the left half of his face are damaged after encountering a trigger-happy Martian and his ray gun. Frank, now the "Frankenstein" of the title, described by his creator as an "astro-robot without a control system", proceeds to terrorize the island. A subplot involves the Martians abducting bikini-clad women.
The "Space Monster" of the title refers to a radiation-scarred mutant named Mull brought along as part of the Martian invasion force. The android and Mull battle each other at the end of the film and both are destroyed.