With the development of social networks, emojis have become an important tool for people’s daily communication. Sometimes it is difficult for us to express emotions to each other through words. Emojis can solve the “double blind” embarrassment of cross-screen interaction. Now that emojis are not limited to social communication, they have also begun to be widely used in the product marketing field. Two experiments are designed in this research to investigate whether positive emojis can promote consumers’ purchase intentions and explore the mediator effect of involvement and moderator effect of product type. Before the formal study, a pre-survey on the usage trend of emojis had been done. The survey showed that more than 90% of consumers use emojis more frequently. Most of them show a positive attitude and a high evaluation of the use of positive emojis in product design, and think that positive emojis are more suitable for FMCG (Fast Moving Consumer Goods), not luxury goods, such as specific performance in the three categories of food and beverage, daily necessities and clothing. But positive emojis are not applicable to electronic products, luxury goods and other valuables. Study 1 attaches positive emojis to products to explore the influence of positive emojis on purchase intention in product design. This study used a single-factor inter-subject design. In this study, 202 subjects were recruited, 15 subjects who did not answer seriously were excluded, 47 subjects were excluded from group manipulation of independent variables, and 140 subjects remained, which was divided into three groups: positive emoji group (n = 39), blank control group (n = 61) and pattern group (n = 40). It was found that positive emojis in the design of products increased consumers’ involvement, and thus increased their purchase intention, compared with blank controls and patterns (Mpositive emoji group = 4.78, SDpositive emoji group = 1.42; Mpattern group = 3.76, SDpattern group = 1.27; Mcontrol group = 3.09, SDcontrol group = 1.17; F(2,136) = 22.30, p < 0.001, η2p = 0.25). On the basis of Study 1, Study 2 added the moderating variable——product type (hedonic/utilitarian) to further explore whether there are boundary conditions for the influence of positive emojis on consumers’ purchase intention. Slightly different from Study 1, Study 2 used positive emojis in product advertisements and divided the products into hedonic products and utilitarian products to explore the effect of positive emojis on purchase intention in different product types. This study adopted a 2×2 inter-subject design. 212 subjects were assigned randomly to one of four conditions: positive emoji-hedonic (n = 52), positive emoji-utilitarian (n = 54), non-emoji-hedonic (n = 53), non-emoji-utilitarian (n = 53). Studies have shown that positive emojis can further increase consumers’ intention to purchase hedonic products, while when the products are utilitarian, the presence or absence of positive emojis has a relatively small effect on consumers’ purchase intentions (t(210) = 6.40, p < 0.001, d = 0.13). Examining the model of moderated mediating effect, it was found that the process of positive emojis influencing the purchase intention through the involvement is moderated by the product type, and there was a moderated mediating model. Through two experiments, this study revealed that under two marketing methods, product design(Study 1) and advertising(Study 2), positive emojis have a positive impact on consumers’ purchase intention, and positive emojis further improve consumers’ purchase intention by increasing their involvement. And positive emojis are more likely to increase consumers’ purchase intention to hedonistic products than utilitarian ones.