Depression is a widespread and serious mental health condition commonly treated with pharmacotherapy as a first-line approach. However, antidepressant medications often require more than two weeks to produce noticeable effects and may be contraindicated in certain populations, such as pregnant women. Many individuals with depression experience sleep disturbances and disruptions in circadian rhythms. In this context, chronotherapy—which aims to resynchronize circadian rhythms—has demonstrated potential for facilitating rapid mood improvement. Key chronotherapeutic interventions that have demonstrated some degree of effectiveness include light therapy, sleep deprivation therapy, sleep phase advance therapy, and triple chronotherapy, which combines all three modalities. Although chronotherapy is generally regarded as effective, the current body of evidence is limited by a lack of systematic and large-scale studies. Therefore, further research is needed to establish its efficacy more robustly. Moreover, future investigations should explore the potential of digital chronotherapy tools based on ICT, which may offer greater convenience for both patients and healthcare providers.