The Queen of Soul’s office said doctors have advised the recovering musician to undergo tests.
Franklin had said in a statement Tuesday she was "very much looking forward to being in Brooklyn and having a foot-long hot dog at Coney Island."
Her office said she will make up the concerts set for Monday at Wingate Field in East Flatbush and August 12 at Asser Levy Park in Brighton Beach.
The “Respect” singer was also set to perform at an Aug. 11 birthday party for U.S. Rep. Charles Rangel, D-N.Y.
Last week, Franklin performed with ex-Secretary of State Condoleezza Rice at a children's programs fundraiser in Philadelphia.