Abstract: Cellulose, being the most abundant natural polymer on Earth, boasts numerous superior properties such as renewability, complete biodegradability, and biocompatibility, thus finding extensive application in various aspects of production and daily life. The molecular weight parameters critically influence a range of properties of cellulose materials, including mechanical properties, rheological properties, and crystallization behaviors. Accurate measurement of these parameters is vital for the design, processing, and application of cellulose materials. This paper reviews the structural characteristics of cellulose, discusses the influence of molecular weight parameters on cellulose material properties, and summarizes the principles and current status of existing methods for measuring these parameters in cellulose materials. Emphasis is placed on advanced measurement methods based on novel solvent systems, and the future prospects of establishing a universal, standardized method for cellulose measurement are presented.