Squeeze out juice from oranges or lemon, keep aside.
Cut Mangoes into pieces roughly. If you are using the mangoes that contains lot of fibrous strings, I recommend to pulp out using strain method. See the images for reference.
Into the blender, add cut mangoes, orange juice and blend till smooth. Add water as needed and blend one more time to mix everything really well.
Refrigerate Mango juice for up to 3 days or freeze for longer.