Cassava (Manihot esculenta Crantz) is the third highest-yielding source of carbohydrates among the world’s crops. In Paraguay, it is a staple food in the Paraguayan diet and the second source of starch after corn, with high demand. In this study, the percent composition of 12 cassava accessions from the germplasm bank of the Paraguayan Institute of Agricultural Technology was determined. The percent composition was determined in freeze-dried samples using the methodology of the Association of Official Analytical Chemists (AOAC), and carbohydrates were determined by difference. The results highlight that cassava is composed primarily of water and carbohydrates. It is a moderate source of dietary fiber, low in protein, and fat-free. The moisture, protein, ash, and dietary fiber contents differ significantly (p ≤ 0.01) among the cassava samples. The cassava accessions evaluated show significant variations among samples in terms of moisture, protein, ash, and dietary fiber, highlighting their diversity and the potential for differential use in food product improvement and development programs.