233 Himalayan Economics and Business Management Research Article The Effect of Flash Sale on Online Impulse Buying Mediated by Positive Emotion in Shopee Users (Case Study on Gen Y) Khofifah Rahmania 1 , Juniwati 2 , Bintoro Bagus Purmono 3 , Harry Setiawan 4 , M.Irfani Hendri 5 Faculty of Economics and Business, Universitas Tanjungpura, Pontianak, Indonesia INTRODUCTION Technology development in the current digital era has brought rapid changes in aspects of human life. One of them is the internet, which has been utilized as a medium for online shopping, which has increased the number of customers who buy online each year in Indonesia. A study survey conducted by the Indonesian Internet Service Providers Association (APJII) found that by the year 2020, the number of internet users in Indonesia reached 73% of the population, equivalent to approximately 200 million users. Additionally, 54% of the population comprises generation Z and generation Y members who enjoy a digital lifestyle. According to Kotler & Keller (2016), the term "e-commerce" refers to the use of a website to conduct or enable the selling of goods and services over the internet. People are encouraged to make unplanned purchases due to the ease and rewards offered by e-commerce, which leads to impulse buying (Wahyuni & Setyawati, 2020). Consumers purchase a product without a plan due to the emergence of marketing stimuli such as attractive promotions or discounts (Ahn & Kwon, 2020). Hashmi et al., (2019) define online impulse buying behavior as a desire or decision to buy a product spontaneously. The term "Generation Y" refers to those who came of age during and immediately after the proliferation of the internet (Lyson, 2004). According to Schmidt (2000), the Y generation, or millennials, were born between 1981 and 1994. The Y generation is highly comfortable using technology such as social media, and applying it to life. In addition, they have several qualities, including being creative, informative, productive, dynamic, practical, open-minded, and consumptive (Putra, 2016). Compared to previous generations, Generation Y is more likely to engage in compulsive and impulsive buying (Research in Action, 2004). In online retail, a "flash sale" is a type of limited-time event that offers steep discounts on various products, such as those not limited to consumer electronics, clothes, and other items (Joshi & Domb, 2017). A flash sale is a type of limited-time sale that offers products at prices lower than their typical prices for a limited number of products for a limited amount of time (Gu et al., 2015; Zhang et al., 2018). Vannisa et al, (2020) demonstrate that the limited amount of time and products available in the flash sale program can affect impulsive product purchases. A person with strong purchasing habits is likely to feel motivated by a flash sale program, which leads to them making purchases impulsively or spontaneously (Darwipat & Syam, 2020). As a result, this type of offer is targeted toward price-conscious customers who frequently do not make plans to make purchases in advance, to entice them to make impulsive purchases (Zhang et al., 2018). Flash sales can also benefit the online market as they can increase the number of visitors and revenue (Agrawal & Sareen, 2016; Sujata & Menachem, 2017). The intensity of consumer spending can be influenced by the consumers' level of positive feeling, which is their mood. Customers are more likely to purchase when they are in a good mood. (Diany et al., 2019). When consumers experience pleasant emotions, those pleasant emotions will encourage consumers to make purchases on the spur of the moment. On the other hand, when consumers experience unpleasant emotions, those unpleasant emotions will not encourage consumers to make purchases on the spur of the moment (Anggriawan et al., 2016). The involvement of *Corresponding Author Khofifah Rahmania Article History Received: 21.01.2023 Accepted: 30.01.2023 Published: 13.02.2023 Citations: Khofifah Rahmania, et al., (2023); The Effect of Flash Sale on Online Impulse Buying Mediated by Positive Emotion in Shopee Users (Case Study on Gen Y). Hmlyan Jr Eco Bus Mgn; 4(1)233- 240. Abstract: Impulsive behavior among Indonesians, particularly among members of generation Y, has been attributed to the rise of online purchasing. Consumer impulsivity has the potential to become a prospective market segment, allowing e-commerce to generate promotional activities such as flash sales to drive shoppers' propensity toward an impulsive purchase behavior. This research aims to prove the effect of flash sales on online impulse buying mediated by positive Emotions on generation Y. This research employed causal research design as part of used quantitative research methods. The questionnaire was distributed to a total of 205 people who fulfilled the purposive sampling criteria as Shopee users in the generation Y category. Data were analyzed using the Structural Equation Model (SEM) with the AMOS 26 program. The findings revealed that flash sales and positive emotions significantly affect generation Y's online impulse buying behavior at Shopee, and positive emotions mediate this effect. Keywords: Flash Sale; Positive Emotion; Online Impulse Buying; Generation Y Open Access