The invention provides a method for extracting iodine from chloride-calcium type oil field water by an air blowing process. The method comprises the following steps: acidifying and oxidizing the chloride-calcium type oil field water to transform iodine ions into elementary iodine, then blowing the elementary iodine out by the air blowing process and absorbing the elementary iodine from iodine-containing air by alkali liquor; acidifying absorption liquid to obtain a wet crude iodine product; and filtering, cleaning and drying the wet crude iodine product to obtain a high-quality iodine product. The method has relatively simple process, convenient operation, low energy consumption and low cost and helps realize industrialization of iodine extraction from the oil field water.