Aims: Data regarding the cardiac toxicity of cabozantinib lacks. The aim of our study was to assess the risk of cabozantinib‐related cardiotoxicity in mRCC patients.Methods: We performed a multicentre prospective study on mRCC patients treated with cabozantinib between October 2016 and November 2017. Transthoracic echocardiogram and plasma biomarkers assay were assessed at baseline, 3 and 6 months after cabozantinib initiation.Results: The study population included 22 mRCC patients. At baseline, 9.1% had a reduced left ventricular ejection fraction (LVEF), but none had a left ventricular systolic dysfunction. Patients with baseline reduced LVEF did not show further significant LVEF modification after 3 months. After 6 months, only 1 had an LVEF decline >10% compared to baseline, resulting in LV systolic dysfunction. At baseline, 64.7% and 27.3% of patients had elevated precursor brain natriuretic peptide (proBNP) and high‐sensitivity troponin I (hsTnI), respectively. Among patients with basal normal proBNP and hsTnI, none had elevated values at 3 and 6 months. No correlation was found between basal elevated proBNP and basal reduced LVEF (P = .29), and between elevated proBNP and reduced LVEF after 6 months (P = .37). Similarly, we found no correlations between elevated hsTnI and reduced LVEF or elevated proBNP at baseline (P = .47; P = .38), at 3 (P = .059; P = .45) and after 6 months (P = .72; P = 1.0).Conclusions: This prospective study revealed a modest risk of developing left ventricular systolic dysfunction related to cabozantinib. A lack of correlation between elevated cardiac biomarkers and reduced LVEF at different time‐points was detected. Assessments of the cardiac function should be reserved at the occurrence of clinical symptoms.