发育生物学（英语：Developmental biology）是对于生物体生长和发育过程的研究。发育生物学研究基因对细胞生长，分化和形态发生（Morphogenesis）的调控，这些过程使生物体形成组织和器官。胚胎学（Embryology）有时被比较明确地规范到生物体单一细胞阶段，到独立个体之间的研究。直到20世纪，胚胎学是一个比较偏重述叙的科学。时至今日，胚胎学或发育生物学处理讨论一个生物体，如何形成个体正确及完整形态的各个步骤。进入21世纪70年代以后，发育生物学的研究主要着重于分子和细胞生物学水平上的胚胎学。

Developmental biology is the study of the process by which animals and plants grow and develop, and is synonymous with ontogeny. In animals most development occurs in embryonic life, but it is also found in regeneration, ****ual reproduction and metamorphosis, and in the growth and differentiation of stem cells in the adult organism. In plants, development occurs in embryos, during vegetative reproduction, and in the normal outgrowth of roots, shoots and flowers. Practical outcomes from the study of animal developmental biology have included in vitro fertilization, now widely used in fertility treatment, the understanding of risks from substances that can damage the fetus (teratogens), and the creation of various animal models for human disease which are useful in research. Developmental Biology has also helped to generate modern stem cell biology which promises a number of important practical benefits for human health.