Celiac disease (CD) is a chronic autoimmune disorder induced in genetically susceptible individuals by the ingestion of gluten from wheat, rye, barley or certain varieties of oats. A careful diet follow-up is necessary to avoid health complications associated with long-term gluten intake by the celiac patients. Small peptides (GIP, gluten immunogenic peptides) derived from the gluten digestion, which are excreted in the urine and feces, have emerged as promising biomarkers to monitor gluten intake.We have implemented a simple and sensitive label-free point-of-care (POC) device based on Surface Plasmon Resonance for the direct detection of these biomarkers in urine. The assay employs specific monoclonal antibodies and has been optimized for the detection of the 33-mer -gliadin, known as the main immunogenic peptide of wheat gluten, and for the detection of GIP. Direct detection in undiluted urine has been accomplished by using biosensing chips containing a robust and stable biorecognition layer, obtained after carefully optimizing the biofunctionalization protocol. Excellent Limits of Detection have been reached (1.6 -4.0 ng mL -1 ), which ensures the detection of gluten peptides even when the gluten intake is around the maximum tolerable amount in the digestive tract (< 50 mg) for celiac individuals. No sample pretreatment, extraction, or dilution is required, and the analysis takes less than 15 min. The assay has been validated with real samples. These features pave the way towards an end-user easy-to-handle biosensor device for the rapid monitoring of gluten free diet (GFD) and the follow-up of the health status in celiac patients.