Nutritional status is an independent prognostic factor in immunoglobulin light-chain amyloidosis (AL), but its influence on quality of life (QoL) is unknown. The aim of this cross-sectional study was to investigate the association between nutritional status and QoL in AL patients at diagnosis. One hundred and fifty consecutive patients with biopsy-proven AL were assessed for nutritional status by anthropometry [body mass index, unintentional weight loss (WL) in the previous 6 months and mid-arm muscle circumference (MAMC)], biochemistry (serum prealbumin), and semiquantitative food intake at referral. QoL was assessed by the Medical Outcomes Study 36-item Short Form General Health Survey. The composite physical component summary (PCS) and the mental component summary (MCS) for AL outpatients were 36.2 ± 10.1 and 44.9 ± 11.3, respectively (p < 0.001 for both vs the population norms of 50). In multivariate linear regression models adjusted for gender, age, Eastern Cooperative Oncology Group performance status, the number of organs involved, the severity of cardiac damage, C-reactive protein, energy intake, and WL, PCS was significantly lower for serum prealbumin <200 mg/L and MAMC <10th percentile (adjusted difference 3.8, 95% CI 0.18-7.5, p = 0.040 and 5.3, 95% CI 2.0-8.7, p = 0.002, respectively). MCS was decreased by 0.47 (95% CI 0.18-0.75, p = 0.002) for each kilogram of body weight lost in the previous 6 months. Nutritional status independently affects QoL in AL patients since diagnosis. Nutritional evaluation should be integral part of the clinical assessment of AL patients. Nutritional support intervention trials are warranted in such patients' population.