Occidental's long and short-term rating was upgraded to BBB- and F3, respectively. The international issuer default rating was affirmed at B-.
"These rating actions are driven by the faster than expected recovery of the bank's capitalization ratios, due to a mix of fresh capital injections and increased, though still volatile, profits," the ratings agency said in a statement.
"Capital is the Achilles' heel of the bank, especially when the sizable burden of intangibles (around 75% of its total equity) is considered," Fitch analysts added.
Occidental is Venezuela's sixth largest bank, with about 6% of financial system deposits as of May.