Yes, you can mix beef protein powder with water, although this may not be the most common way to consume it. Mixing beef protein powder with water can help make it more convenient to drink, especially for people who do not like the taste of milk. Additionally, water has a neutral flavor and will not interfere with the taste of the beef protein powder, which can be helpful for those who are sensitive to certain flavors. Water also offers the best low-calorie option, making it ideal for those who are trying to maintain or lose weight.