Place corn into a large pot and cover with water; bring to a boil. Reduce heat to medium-low; simmer until tender, about 5 minutes. Drain; cool corn. Cut kernels from cobs.

Combine corn kernels, avocados, tomatoes, black beans, cilantro, onion, and jalapeño in a bowl.

Whisk olive oil, lime zest, and lime juice together in a bowl; pour over corn mixture and toss to coat. Refrigerate until chilled, about 1 hour.