The aim of the work was to present clinical material referring to rarely occurring abdominal cavity hernias in semilunar line – Spigelian hernias diagnosed with the help of ultrasound.Material and methods: In the period from 1995 to 2001 785 anterior abdominal wall hernias were diagnosed including 11 Spigelian hernias (1.4%) diagnosed in 10 patients (7 women and 3 men) aged from 38 to 65 years old (average age 48). Eight patients complained of spastic pain in abdomen, in 5 of them it was accompanied by bloating and sometimes loud peristalsis. All the patients had been observing the mentioned symptoms from 2 to 5 years. Each of them had had colonoscopy and abdominal cavity ultrasound examination performed, some of them even three times. In 3 women with uterine fibroid the uterus was removed which did not eliminate the symptoms. The ultrasound examination of the abdominal integument was performed mainly with the use of linear transducers of the frequency of 7–12 MHz; in obese patients also convex transducers were used (3,5–6 MHz). Each examination of abdominal integument included the assessment of the following areas: linea alba from xiphoid process to pubic symphysis including umbilicus, both semilunar lines from costal margins to pubic bones, and also inguinal areas. Moreover, all types of postoperative scars were examined. Each hernia was assessed in terms of size (the greatest dimension), hernia sac contents, width of the ring and reducibility under the compression of the transducer. Moreover, cough test and Valsalva’s maneuver were performed. Generally, the examination was performed in a standing position. Results: In 9 patients hernias were localized unilaterally, in one patient bilaterally. In 7 cases the hernia sac contained small bowel, in 2 cases the preperitoneal and omental fat, and in 2 cases preperitoneal fat only. Eight patients presenting with clinical symptoms underwent operative repair. Conclusion: Ultrasound examination is beneficial in confirming the diagnosis of Spigelian hernias especially in terms of proper, therapeutic decision‑making.