At present, the approaches for flower and fruit thinning mainly rely on manual labor and chemical thinning methods. The manual approach entails high labor intensity, elevated labor costs, and low efficiency; the chemical thinning method, when applied in large quantities, can pollute the environment. Thus, over the past few decades, efforts have been made to enhance the fruit-thinning methods and progress has been achieved in aspects such as mechanized and intelligent fruit thinning. Nevertheless, there is a scarcity of extensive overviews regarding the research progress of fruit-thinning equipment. Therefore, this study aims to summarize the research advancements in flower and fruit-thinning equipment as well as the key technologies in a comprehensive manner. Currently, the research on intelligent fruit-thinning equipment is still in its nascent stage. Hence, this paper compiles the key technologies of current handheld mechanized equipment, vehicle-mounted mechanized equipment, and intelligent equipment, including the studies on visual systems, motion planning, and end effectors, along with the research progress of complete intelligent equipment. In the future, intelligent fruit-thinning equipment is anticipated to move further towards intelligence and automation and can achieve precise fruit thinning in complex orchard environments.