Writing a gratitude journal is an effective way to boost positive affect. However, little is known about what factors drive people to engage in this activity and whether such factors are related to the outcomes of the activity. This investigation attempted to answer these two questions. We proposed that two beliefs about emotion—desirability of happiness and uncontrollability of negative emotion—motivate people’s engagement in a gratitude journal. We recruited 311 participants online and examined whether and via what paths people’s beliefs about emotion translated to their voluntary initiation of a gratitude journal. We further tested (among those who initiated a journal) whether the emotional outcomes of writing a journal could be predicted by their beliefs about emotion (n = 101). The results showed that the desirability of happiness belief predicted the initiation of a gratitude journal via both the attitude-intention and the subjective norm-intention paths. Furthermore, this belief was positively related to the change in people’s ideal positive affect after writing the journal. In contrast, the uncontrollability of negative emotion belief did not predict journal initiation because the negative effect through the perceived behavioral control-intention path and the positive effect through the intention-only path canceled each other out. Furthermore, this belief was positively related to the change in people’s actual positive affect after writing the journal. Together, the findings delineate an emotion belief-to-emotion regulation behavior link and the consequences of such behavior. Implications for the design of gratitude journals specifically and positivity activity interventions generally are discussed.

写感恩日记是增强积极影响的有效方法。然而，关于是什么因素促使人们参与这项活动以及这些因素是否与活动的结果有关，我们知之甚少。本次调查试图回答这两个问题。我们提出了两种关于情绪的信念——对幸福的渴望和消极情绪的不可控性——激发了人们对感恩日记的参与。我们在网上招募了 311 名参与者，并检查了人们对情绪的信念是否以及通过什么途径转化为他们自愿开始写感恩日记。我们进一步测试（在那些开始写日记的人中）写日记的情绪结果是否可以通过他们对情绪的信念来预测（n = 101）。结果表明，幸福信念的可取性通过态度-意图和主观规范-意图路径预测了感恩日记的开始。此外，这种信念与写日记后人们理想的积极情绪的变化呈正相关。相比之下，消极情绪信念的不可控性并不能预测期刊的开始，因为通过感知行为控制-意图路径的负面影响和通过仅意图路径的积极影响相互抵消。此外，这种信念与写日记后人们实际积极影响的变化呈正相关。总之，这些发现描述了情绪信念与情绪调节行为之间的联系以及这种行为的后果。