Yes, you can use this spray on dry hair to help with frizz and static. The source mentions that the formula includes aloe leaf juice and yeast extract, which add a conditioning element that helps hair that gets fluffy, static, or unruly in humid weather or after heat styling. Because it is a spray, it is easy to apply to dry hair without overloading it. For best results, spray a small amount onto your hands or directly onto the hair, then smooth it over the surface. Be careful not to apply too much, as it can make the hair look slightly sticky or wet. If you are using it after heat styling, wait until the hair has cooled down before applying, because spraying on hot hair can cause the product to evaporate or feel sticky. This spray is not a heat protectant, so it does not protect against heat damage; you would still need a separate heat protectant if you use hot tools. The effect is mainly cosmetic: it helps the hair look smoother and feel softer, but it does not change the hair structure. This product is not intended to treat any hair or scalp disease.