The invention belongs to the field of daily chemicals. A green alga-containing scalp-soothing nursing agent is prepared from the following components: glycerol, a green alga extract, ethanol, silicone oil, peppermint oil, menthyl lactate, copper chlorophyllin, a thickening agent, an ampholytic surfactant, a nonionic surfactant, a cationic conditioner, a plant extract and the balance of water. The nursing agent is mild and is low in irritation, the deposition rate of effective components is high, and the conditioning effect is lasting; the cleaning effect is good, oil control and moisture preservation are achieved, scalp water-oil balance is adjusted, a sebum film is rebuilt, scalp barriers and damaged hair are repaired, and scalp is helped to resist external stimulation; anti-inflammation and bacteriostasis are achieved, and scalp inflammation is relieved; the nursing agent can be used for activating, resisting aging, promoting cell proliferation and differentiation, increasing the number of hair follicles with complete structures, and growing hair; hair roots are nourished, and the hair is fixed and prevented from hair loss; and the skin feeling is fresh, cool, non-sticky and non-greasy, after being used, the hair is cool and refreshing, and the hair is fluffy and smooth.