The invention relates to application of a cis-form reductone dioxygenase gene OsARD1 in improvement of the drought resistance ability of rice. The cis-form reductone dioxygenase gene is characterized in that a nucleotide sequence of the OsARD1 is shown as SEQ ID No.1, and the amino acid sequence encoded by the gene OsARD1 is shown as SEQ ID No.2. It is found through an experimental result that the tolerance of an overexpression plant to PEG processing is strong, and it is indicated that the tolerance ability of the rice to osmotic stress is obviously improved through OsARD1 overexpression. It is further indicated through an experiment that the drought resistance ability of the rice can be improved to some degree through OsARD1 overexpression. The drought resistance ability of crops is improved by utilizing a transgenosis strategy, a drought-resistant crop variety is bred, the crop yield is increased, and the application has the important significance on guarantee of grain production safety.