Background Development of genetically modified crops has rapidly increased in last few years. The most widely grown GM crops express genes that confer herbicide tolerance and insect resistance. Detection system of GM crops is important for safety evaluation before its consumption. Objective The purpose of this research is to detect GM crops, especially PAT, in food-samples. Results The bar gene (PAT protein, herbicide resistant) was cloned in pGEX-4T-1 and expressed by E. coli. The high-affinity PAT-specific single-stranded DNA (ssDNA) aptamers were obtained from a random DNA library. MOE docking study was performed to identify the potential binding region of the selected aptamers on PAT. Aptamer-linked immobilized sorbent assay (ALISA) method was used to detect PAT. Conclusion We screened aptamer against PAT for developing an efficient detection method. The selected PAT specific aptamers, HRPA-05 and HRPA-07, showed the distinct target binding behaviors, and detected PAT protein by aptamer-linked immobilized sorbent assay method with high efficiency and selectivity.