The invention discloses watermelon scented blackening shampoo. The watermelon scented blackening shampoo comprises the following components in parts by weight: 1 to 2 parts of pearlescing liquid, 3 to 4 parts of potassium salt, 0.1 to 0.2 part of a radix polygoni multiflori extract, 0.04 to 0.08 part of clove oil, 0.2 to 0.4 part of wire drawing powder, 0.5 to 1 part of potassium sulfide, 0.4 to 0.6 part of ketoconazole, 0.3 to 0.4 part of trisodium citrate, 0.7 to 0.8 part of hydrolyzed amyloprolamine, 0.4 to 0.8 part of glycerol, 10 to 22 parts of olive oil, 3 to 7 parts of cucurbocitrin and the balance of water. The watermelon scented blackening shampoo disclosed by the invention has beneficial effects: the process is simple; the detergency is moderate; rinsing is easy; no irritation to hair, skin and eyes is caused; washed hair is bright, smooth, soft, elastic and good in combability when the hair is in dry and wet states; users especially feel cool, refreshing, comfortable and relaxed; and the watermelon scented blackening shampoo further has the effects of relieving itching, preventing or inhibiting dandruff regeneration, refreshing and restoring consciousness, nourishing heart and soothing nerves.