Here we reported a 64-year-old male patient with synchronous triple primary malignant tumours of the bladder urothelial carcinoma, prostate adenocarcinoma, and non-small cell lung cancer (NSCLC) with mutations in TP53 and MEK1, all the three malignancies were diagnosed within 10 days. Here, MAP2K1 is linked to bladder transitional cell carcinoma.