Leucine-rich repeat (LRR) is widely present in various organisms, mainly involved in the innate immune process. To further study its mechanism, it is necessary to prepare an antibody that can specifically recognize LRR structure. Chlamydomonas reinhardtii as a model organism, the physicochemical properties of CrLRR-1 protein including secondary structure, hydrophilicity, immunogenicity were predicted and analyzed by bioinformatics. CrLRR-1 specific peptide was designed and synthesized, which coupled with keyhole limpet hemocyanin (KLH) was used to immunize New Zealand white rabbits. The antiserum titer was determined to be 1:512 000 by indirect ELISA and the antiserum was purified by Protein A and antigen affinity. The results of western blotting and immunofluorescence showed the polyclonal antibody could specifically recognize to LRR-1 in C. reinhardtii, and the CrLRR-1 protein is mainly located in the cell membrane. In conclusion, polyclonal antibody against CrLRR-1 protein was successfully prepared.