The process of exploring and committing to one’s identity for the sake of a future-oriented goal is important for young adults’ psychosocial functioning. Whereas the relationship between identity process and psychosocial functioning has been examined in long-term longitudinal studies, the short-term relationship between the two at the daily level has not been clarified. This study developed a measure of daily-level identity process and examined their relationship with daily positive and negative emotions, using a five-day daily-diary method. The participants included 721 Japanese young adults aged 18–30 years (54.4% female, M_age = 26.05 years). Results indicated the measure’s three-factor structure, including commitment, active exploration, and ruminative exploration. Commitment related positively to life satisfaction and happiness, and negatively related to depression. Active exploration and ruminative exploration indicated negative associations with life satisfaction and happiness, and positive association depression. Latent profile analysis extracted five theoretically meaningful identity profiles at the daily level: foreclosure, moratorium, troubled diffusion, searching moratorium, and carefree diffusion. Logistic regression analyses indicated that troubled diffusion and moratorium, and foreclosure profiles showed lower and higher levels of life satisfaction and happiness, respectively. These results provided evidence of a strong link between young adult’s identity processes, profiles, and positive and negative emotions at the everyday level. Implications and suggestions for future research are discussed.

为了面向未来的目标而探索和承诺自己的身份的过程对于年轻人的心理社会功能很重要。虽然身份过程和心理社会功能之间的关系已经在长期纵向研究中进行了检验，但两者在日常层面上的短期关系尚未得到澄清。本研究开发了一种日常认同过程的测量方法，并使用五天日记法检查了它们与日常积极和消极情绪的关系。参与者包括 721 名 18-30 岁的日本年轻人（54.4% 的女性，M_年龄） = 26.05 年）。结果表明该测量的三因素结构，包括承诺、积极探索和反刍探索。承诺与生活满意度和幸福感呈正相关，与抑郁呈负相关。积极探索和反刍探索表明与生活满意度和幸福感呈负相关，而与抑郁呈正相关。潜在概况分析在日常层面提取了五个理论上有意义的身份概况：止赎、暂停、麻烦扩散、搜索暂停和无忧扩散。逻辑回归分析表明，问题扩散和暂停，以及止赎。个人资料分别显示出较低和较高的生活满意度和幸福感。这些结果提供了证据，证明年轻人的身份过程、个人资料以及日常积极和消极情绪之间存在密切联系。讨论了对未来研究的影响和建议。