The invention relates to membrane technologies and discloses a recycling technique and device for waste acid of an anodizing process. The technique comprises the following steps that firstly, the waste acid from an anodizing cell is cooled, and the temperature of subsequent procedures is controlled; secondly, the cooled waste acid is subjected to coarse filtration, and suspended matter in the waste acid is removed; and thirdly, the waste acid subjected to coarse filtration is filtering separation through a membrane technology, and a concentrated solution and filtrate are obtained. The filtrateis recycled for an anodizing technique. Through the recycling technique, the application efficiency of acid in the anodizing technological process can be improved, and discharge of waste acid in theanodizing process is reduced.