Spontaneous diaphragmatic rupture (SDR) is a very rare surgical emergency. A possible explanation for SDR might be a sudden increase of intra-abdominal pressure due to intense coughing, physical exercise, vomiting, or delivery. A 66-year-old male patient presented with recurrent coughing, dyspnoea, and intermittent fever. Although initial CT scan was inconspicuous, a follow-up CT scan revealed SDR of the left hemidiaphragm with herniation of the left colonic flexure, stomach, and parts of the greater omentum. Emergency laparotomy confirmed SDR. The ruptured anterior-lateral part of the diaphragm was closed, and additionally, a composite mesh was applied to reinforce the suture line. A right-sided hemicolectomy with primary anastomosis had to be performed. SDR is a rarity and can cause exceptional clinical features that may lead to inaccurate diagnosis and therapeutic delay. Therefore, of paramount importance, medical practitioners need to be aware of this important differential diagnosis for spontaneous dyspnoea or tachypnea.