Abstract: The evolution process of the solar wind is an important topic in space physics. High-frequency electrostatic waves have attracted wide attention because they are closely related to the distributions of the solar wind particles. The recently launched Parker Solar Probe (PSP) has observed a variety of high-frequency electrostatic waves in the near-Sun solar wind (solar distance r<0.3AU), which provides a new opportunity to study the wave-particle interactions therein. In this review, we introduce the research status of high-frequency electrostatic waves, summarize the observational features of each wave, including the well-known ion-acoustic waves, electron Bernstein waves and some unknown electrostatic waves. We also discuss the possible excitation mechanisms or free energy sources of each wave. Besides, we present our perspectives on the topic.