Obama, who made a groundbreaking visit to Myanmar in 2012, announced the renewal yesterday in a letter to Congress.
The sanctions bar American companies and citizens from investing in the country formerly known as Burma.
They also mean Americans cannot do business with Myanmar leaders identified as having repressed pro-democracy sentiment in that nation formerly run by a tough military junta.
Yesterday Obama said Myanmar has made significant progress in a number of critical areas.
These include the release of over 1,100 political prisoners, progress towards a nationwide ceasefire, legalisation of unions, steps to improve the country's labour standards, and allowing greater freedom of association and expression, Obama said.
Obama said: "The political opening remains nascent, and concerns persist regarding ongoing conflict and human rights abuses in ethnic minority areas, particularly in Rakhine State, and the continued role of the military in the country's political and economic activities.