Type 2 diabetic cardiomyopathy (DCM) has been linked to Ca2+ signaling alterations, notably a decreased mitochondrial Ca2+ uptake. Uncovering of Ca2+ microdomains between cardiac mitochondria and reticulum launched a new investigation avenue for cardiometabolic diseases. We here aimed to study if the impairment of mitochondrial Ca2+ handling could be due to a dysregulation of the reticulum-mitochondria interactions or of the mitochondrial Ca2+ uniporter in the diabetic mice heart. Phenotypic alterations of the type 2 diabetic mouse heart, was done using an in vivo obesogenic high fat high sucrose diet fed mouse model (HFHSD: 20% proteins, 36% lipids). The composition of the cardiac MAM fractions between standard diet-fed (SD) mice and HFHSD (HF) mice at 16 weeks was analysed by MS-based quantitative proteomics.