Preoperative malnutrition in patients with colorectal cancer is associated with several postoperative consequences and poorer prognosis. Currently, there is a lack of a universal screening tool to assess nutritional status, and intervention to treat preoperative malnutrition is often neglected. This review summarizes and compares preoperative screening and interventional tools to help providers optimize malnourished patients with colorectal cancer for surgery. We found that nutritional screenings, such as the Subjectibe Global Assessment, Patient-Generated Subjective Global Assessment, Prognostic Nutritional Index, Nutrition Risk Index, Malnutrition Universal Screening Tool, Nutrition Risk Screening 2002, Nutrition Risk Score, serum albumin, and prealbumin, have all effectively predicted postoperative outcome. Physicians should consider which of these tools best fits their needs based on the their mode of assessment, efficiency, and specified parameters. Additionally, preoperative nutritional support, such as trimodal prehabilitation, modified peripheral parenteral nutrition, and N-3 fatty acid and arginine supplementation, which have also benefited patients postoperatively, ought to be implemented appropriately according to their ease of execution. Given the high prevalence of preoperative malnutrition in patients undergoing surgery for colorectal cancer, it is essential that health care providers assess and treat this malnutrition to reduce postoperative complications and length of hospital stay, and to improve prognosis to augment a patient's quality of care.La malnutrition preoperatoire chez les patients atteints d'un cancer colorectal est associee a plusieurs complications postoperatoires et a un pronostic plus sombre. Il n'existe actuellement aucun outil universel d'evaluation du statut nutritionnel, et les mesures visant a corriger la malnutrition preoperatoire font souvent defaut. La presente revue resume et compare les outils de depistage et d'intervention preoperatoires pour aider les professionnels a ameliorer l'etat des patients denutris qui doivent subir une chirurgie pour le cancer colorectal. Nous avons constate que le depistage nutritionnel a l'aide de questionnaires tels que l'Evaluation globale subjective, l'Index nutritionnel pronostique, l'Outil universel de depistage de la malnutrition, NRS 2002 (Nutrition Risk Screening 2002), l'evaluation du risque nutritionnel, et le dosage de l'albumine et de la prealbumine seriques, a permis de predire avec justesse l'issue de la chirurgie. Les medecins devraient verifier lequel de ces outils est le mieux adapte a leurs besoins selon leur modalite d'evaluation, leur efficience et autres parametres specifiques. Egalement, un soutien nutritionnel preoperatoire, comme la preadaptation trimodale, la nutrition parenterale peripherique modifiee et les supplements d'acides gras N-3 et d'arginine, qui ont aussi donne des resultats postoperatoires favorables, devrait etre applique selon sa facilite d'administration. Etant donne la forte prevalence de la malnutrition preoperatoire chez les patients soumis a une chirurgie pour cancer colorectal, les professionnels de la sante se doivent d'evaluer et de corriger la malnutrition afin de prevenir les complications postoperatoires, d'abreger la duree du sejour hospitalier, et d'ameliorer ainsi le pronostic et la qualite des soins.