Commander Sarah West was a headline appointment when she became the first female commander of a frontline warship in the 500-year history of the Royal Navy.
She described taking on the role as the greatest achievement of her career, adding: "I'm looking forward to taking HMS Portland on operations with a professional and focused team."
Earlier this year she said her work commitments made it difficult to have a relationship.
She told the Daily Mirror: "Years at sea probably explains why I'm single. But every person in the military makes sacrifices."