The invention discloses a method for controlling Dunaliella viridis in a large-area Dunaliella salina culture pond. The method comprises the following steps: 1) sprinkling quicklime into the culture pond, introducing brine with a baume degree of 20 to 24 DEGs into the culture pond to a water depth of 20 to 30 cm and carrying out evaporation to concentrate the brine to a baume degree of 26 to 28 DEGs, wherein salt crystals are precipitated at the bottom of the pond; 2) injecting water to adjusting the salinity of the brine to a baume degree of 20 to 24 DEGs; and 3) inoculating the pond with Dunaliella salina with a certain density, allowing Dunaliella salina to have population advantages, and controlling salinity, the addition amount of nutritional salts and the growth of Dunaliella viridis so as to produce a Dunaliella salina product with a high carotene content, wherein the carotene content finally reaches 8 to 12 mg/L after culture.