The invention relates to application of a partial sequence of protocadherin1 (pcdh1) gene in preparation of a polyclonal antibody and expression detection, and in particular relates to a method for preparing an antibody. The method disclosed by the invention comprises the following steps: carrying out PCR (Polymerase Chain Reaction) amplification on the partial sequence of chicken pcdh1 gene, inserting the partial sequence into an expression vector, performing prokaryotic expression and affinity purification of fusion protein in colibacillus E.coliBL21, mixing and emulsifying the purified protein and a freund's complete adjuvant, and subsequently performing multi-point injection on immunity SD (Sprague Dawley) rat via parts such as foot pads, and quickly producing a specific antibody directed against a target antigen. By adopting immune serum quickly manufactured by the method disclosed by the invention to detect the expression of the pcdh1 gene in chick embryos in different developmental stages, the polyclonal antibody manufactured by adopting the method disclosed by the invention on account of partial peptide fragment of the pcdh1 protein can be expected to be an effective tool for detecting expression of the pcdh1 gene protein.