"Ms Aminata Toure's functions have been terminated," said a decree signed by President Macky Sall yesterday, a copy of which was obtained by AFP.
An official at the president's office said that the resignation of the prime minister "means that the government has been dissolved".
Toure, who is 51, is the head of the Alliance for the Republic and was named prime minister last year to replace incumbent Abdoul Mbaye.
Her departure comes less than a week after preliminary results from the June 29 local elections showed defeats for the APR in Dakar and a number of key cities across the country. Official results are still being awaited.
More From This Section
More than 5.3 million people were eligible to vote for more than 2,700 councillors across the country.
"Since her defeat by Khalifa Sall, (she) has been in the hot seat," RTS national radio commented.
However, the governing "Benno Bokk Yaakaar" (Together With The Same Hope) coalition reportedly won in more than 70 percent of the country's constituencies.
Toure has degrees in economy and management from universities in Senegal, France and the United States and worked for the United Nations in several countries.
In her government policy statement in October, Toure promised to meet social demands and restart the country's economy.