In recent years, with the economic development, people’s living standards have continuously improved, and obesity, suboptimal health, and other issues have continued to appear and have become the focus of people’s attention. To maintain a healthy body, more people are participating in fitness exercises. However, traditional fitness equipment can be boring and inflexible in its use and does not enable the recording of fitness data, making it difficult for people to monitor fitness data and manage their health information. The design of miniaturized intelligent equipment with comprehensive management will be of great significance in meeting the fitness needs of users and have a wide range of applications. As small fitness equipment, dumbbells are suitable for people of different ages, genders, and physical fitness levels. To increase the fun of dumbbell fitness and realize guidance in dumbbell fitness exercise, we have designed an intelligent dumbbell based on multiple-sensor information fused with wireless communication technology. The intelligent dumbbell can automatically recognize its weight through a pressure sensor and judge fitness exercise through an acceleration sensor. The information is then transmitted by a wireless transmission module to a mobile phone application (app) to realize the intelligent monitoring of dumbbell fitness. At the same time, the user can also set the fitness mode through the mobile phone app to guide the user in exercise and more systematically improve the user’s fitness.