Marketing and advertising messages are often designed to persuade and influence the consumers into purchasing the products or services usually designed based on market segmentation and target consumers. This segmentation may vary but the most common type of market segmentation is based on demographic information such as gender. In toy advertisements, children are the target markets. Research shows that most toy advertisements involve gender stereotypes. Therefore, this paper aims to explore the visual elements of gender stereotypes in children's toy advertisements on social media. Using a case study approach, children's toy advertisements on Mattel's official Facebook page were analyzed from January 2019 to December 2019. A total of 87 relevant advertisements were gathered and subjected to content analysis focusing on gender stereotype characteristics and the presence of boy(s) or girl(s) model(s) in the advertisements. The analysis was conducted based on gender stereotype characteristics and the presence of boy or girl models in the advertisement. The findings showed that advertisements for girl toys are more frequently posted on Mattel's official Facebook page than advertisements for boy toys. Further analysis revealed that the advertisements contained more feminine compared to masculine traits and role behaviors. However, a large majority of the advertised toys do not have emotional behaviors. It was envisaged that the findings of this study could advance our knowledge of gender stereotypes in toy advertisements.