Preheat oven to 375 degrees F and grease a standard bread loaf pan.
In a large bowl, cream together the cream cheese and butter. Add sugar, eggs, and lemon zest and beat until light and fluffy.
In a small bowl, combine flour, baking powder, salt, and cinnamon. Once thoroughly combined, slowly add the dry ingredients and milk to the wet ingredients and fold in the peaches.
Transfer batter to the prepared loaf pan and bake for 50-55 minutes or until an inserted toothpick comes out clean.
Let loaf cool before slicing.