Ifeayi Okowa, governor of the state, in a post on Twitter on Saturday, confirmed the development.
Okowa said the patient, a male, was diagnosed in Asaba, the state capital, and has been placed on isolation.
“We have just confirmed the third case of #COVID19 in Delta State.
The patient, a male, was diagnosed today in Asaba, our state capital, and is currently being managed by our healthcare professionals in one of our isolation centres.
“The patient is currently in a good state and responding to treatment and we have already began to track all those that have had contact with him.
“The confirmation of this third case further reinforces our call for social distancing and a lockdown. All Christians should worship at home tomorrow.”