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In this study, 52 <i>AAAP</i> genes were identified in the <i>L. chinense</i> genome and divided into eight subgroups based on phylogenetic relationships, gene structure, and conserved motif. A total of 48 <i>LcAAAP</i> genes were located on the 14 chromosomes, and the remaining four genes were mapped in the contigs. Multispecies phylogenetic tree and codon usage bias analysis show that the <i>LcAAAP</i> gene family is closer to the <i>AAAP</i> of <i>Amborella trichopoda</i>, indicating that the <i>LcAAAP</i> gene family is relatively primitive in angiosperms. Gene duplication events revealed six pairs of segmental duplications and one pair of tandem duplications, in which many paralogous genes diverged in function before monocotyledonous and dicotyledonous plants differentiation and were strongly purification selected. Gene expression pattern analysis showed that the <i>LcAAAP</i> gene plays a certain role in the development of <i>Liriodendron</i> nectary and somatic embryogenesis. Low temperature, drought, and heat stresses may activate some <i>WRKY/MYB</i> transcription factors to positively regulate the expression of <i>LcAAAP</i> genes to achieve long-distance transport of amino acids in plants to resist the unfavorable external environment. In addition, the <i>GAT</i> and <i>PorT</i> subgroups could involve gamma-aminobutyric acid (GABA) transport under aluminum poisoning. These findings could lay a solid foundation for further study of the biological role of <i>LcAAAP</i> and improvement of the stress resistance of <i>Liriodendron</i>.