Preheat oven to 450°.
Lightly spoon flour into a dry measuring cup; level with a knife. Combine flour, cornmeal, sugar, baking powder, and salt in a medium bowl; cut in butter with a pastry blender or 2 knives until mixture resembles coarse meal. Add buttermilk; stir just until moist.
Turn dough out onto a lightly floured surface. Pat dough into an 8 x 4-inch rectangle. Cut dough by making 1 lengthwise cut and 3 crosswise cuts to form 8 biscuits. Place biscuits, 1 inch apart, on an ungreased baking sheet.
Bake at 450° for 12 minutes or until golden. Serve biscuits warm or at room temperature.