Objective Opioid receptor, a kind of G protein-coupled receptors (GPCRs), mainly mediates an analgesic response via allosterically transducing the signal of endogenous ligand binding in the extracellular domain to couple to effector proteins in the intracellular domain. δ opioid receptor (DOP) is associated with emotional control besides pain control, which makes it an attractive therapeutic target. However, its allosteric mechanism and key residues responsible for structural stability and signal transmission are not completely clear. This paper aims to analyze the structural dynamics and allosteric effects of DOP.Methods Firstly, the relationships between DOP structure dynamics and function were explored by means of residue fluctuations in slow motion mode and fast motion mode from the anisotropic network model (ANM). Then, perturbation response scanning (PRS) was used to identify key residues related to allosteric communication in DOP.Results The DOP segments and functional sodium-binding sites can be well identified by the slowest motion modes, and the key residues that play a crucial role in protein structural stability can be identified by the fastest motion modes. Correlation analysis of residue motions reveals positive correlations between extracellular/intracellular transmembrane helices and loops, which promote the DOP structural stability and the binding of DOP with ligands. Key residues with high sensitivity and high effectiveness in PRS analysis play an important role in the allosteric communication of DOP.Conclusion This work sheds light on the allosteric communication mechanism of δ opioid receptor and provides valuable information for drug design.