Preheat your oven to 350°F (175°C). Grease a loaf pan.
In a mixing bowl, whisk together flour, sugar, baking powder, baking soda, and salt.
In another bowl, combine grated zucchini, vegetable oil, eggs, lemon juice, lemon zest, and vanilla extract.
Pour the wet ingredients into the dry ingredients and stir until just combined.
Pour the batter into the prepared loaf pan and bake for 60 minutes, or until a toothpick inserted into the center comes out clean.
Allow the bread to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.