Yes, you can mix pea protein powder with water. Mixing pea protein powder with water is a convenient and simple way to add protein to your diet. It is important to note that while pea protein powder can be mixed with water, it may not have the same texture and flavor as other protein powders. Some people may find that it has a slightly grainy texture and a slightly bitter taste. To improve the taste, you can mix the powder with fruit or sweeteners. Additionally, it is best to choose a high-quality pea protein powder that is free from additives, artificial sweeteners, and preservatives.