The beam splitter can realize the power path distribution of single or multiple beams of light, and it is one of the most fundamental devices of the optical system, which plays an important role in the construction of interferometers, spectrometers, and optical communication systems. Traditional free-space optical beam splitters face many limitations, for example, common cube beam splitters that rely on birefringence of bulky solid glass, which is difficult to apply to integrated optical systems; In recent years, a variety of planar beam splitters, such as flat beam splitters, grating beam splitters and dichroic beam splitters, have defects such as fixed beam splitting ratio and expensive materials. More recently, the construction of optical beam splitters based on metasurfaces provides a promising scheme for integrated beam splitters. However, the metasurface-based scheme only reports two-port beam splitters (i.e., two output paths), and it is difficult to achieve non-uniform beam splitting (i.e., the deflection angle or power of the output sub beams is not equal). In view of the above background, this laboratory proposes an arbitrary beam splitter based on the dielectric metasurface, which distributes the incident light to multiple output channels with any predefined power ratio while keeping the input and output light frequency, polarization, and lateral spacial mode unchanged. The experimental results show that within the 100nm bandwidth around the design wavelength, the beam splitting efficiency is greater than 74.7%, the beam splitting ratio similarity is greater than 78.4%, and have the characteristics of high beam splitting fidelity, high efficiency and wide frequency band. This work was published on October 18, 2023 in the journal of Advanced Optical Material (IF:10.05). Ph.D. student Tian Tian is the first author of this paper, and Professor Xue Feng and Professor Yidong Huang are the corresponding authors of the paper.