<p>Stressors are ubiquitous, and organisms need to mobilize stress responses to counteract them. Sea cucumbers <i>(Apostichopus japonicus</i>), as invertebrates without a centralized brain, exhibit stress response patterns that remain incompletely characterized. The present study identifies three stress response patterns (fleeing, adhesion, and thanatosis) in sea cucumbers, and characterizes the typical behavioral and physiological responses associated with each pattern. Sea cucumbers exhibited fleeing, adhesion, and thanatosis patterns when they were exposed to specific stressors: conspecific carcass presence, seawater rinsing, and mechanical disturbance, respectively. When exhibiting the fleeing pattern, sea cucumbers displayed significantly shorter time of the first crawl and significantly higher movement speed, accompanied by significantly rising levels of norepinephrine, cortisol, and glucokinase activity. These behavioral and physiological responses enable sea cucumbers to move away from conspecific carcasses more rapidly. When exhibiting the adhesion pattern, sea cucumbers displayed significantly higher adhesion index and movement randomness, accompanied by significantly rising levels of norepinephrine and cortisol, and significantly reduced level of gamma-aminobutyric acid (GABA). These behavioral and physiological responses are conducive to sea cucumbers exploring more areas. Thanatosis, also known as death-feigning, is characterized by tonic immobility in behavioral responses. When exhibiting the thanatosis pattern, sea cucumbers showed significantly longer time of the first crawl, higher curling index, and lower crawling frequency, accompanied by significantly reduced level of epinephrine. These behavioral and physiological responses enable sea cucumbers to mitigate the damages caused by mechanical disturbance through inhibiting movement and curling their bodies. The present study enriches our understanding of the stress response patterns in sea cucumbers.</p>