B-cell lymphomas exhibit a vast variety of clinical and histological characteristics that might complicate the diagnosis. Timely diagnosis is crucial, as treatments for aggressive subtypes are considered successful and frequently curative, whereas indolent B-cell lymphomas are incurable and often need several therapies. The purpose of this review is to explore the current advancements achieved in B-cell lymphomas metabolism and how these indicators help to early detect metabolic changes in B-cell lymphomas and the use of predictive biological markers in refractory or relapsed disease. Since the year 1920, the Warburg effect has been known as an integral part of metabolic reprogramming. Compared to normal cells, cancerous cells require more glucose. These cancer cells undergo aerobic glycolysis instead of oxidative phosphorylation to metabolize glucose and form lactate as an end product. With the help of these metabolic alterations, a novel biomass is generated by the formation of various precursors. An aggressive metabolic phenotype is an aerobic glycolysis that has the advantage of producing high-rate ATP and preparing the biomass for the amino acid, as well as fatty acid, synthesis needed for a rapid proliferation of cells, while aerobic glycolysis is commonly thought to be the dominant metabolism in cancer cells. Later on, many metabolic biomarkers, such as increased levels of lactate dehydrogenase (LDH), plasma lactate, and deficiency of thiamine in B-cell lymphoma patients, were discovered. Various kinds of molecules can be used as biomarkers, such as genes, proteins, or hormones, because they all refer to body health. Here, we focus only on significant metabolic biomarkers in B-cell lymphomas. In conclusion, many metabolic biomarkers have been shown to have clinical validity, but many others have not been subjected to extensive testing to demonstrate their clinical usefulness in B-cell lymphoma. Furthermore, they play an essential role in the discovery of new therapeutic targets.