The omentum has raised a great deal of interest in recent years as it is a unique structure being highly vascular and accepting split skin graft readily. It is being used for various purposes not only within the abdomen but also outside it. However, so far, no work has been done regarding its size, although it is important to know before laparotomy whether there is ample omentum to serve the purpose. This study, in a series of 300 cases, not only determines the range of length and width of the omentum, but also correlates them with the height and wight of the patient so that one is able to predict the size, within limits, before laparotomy.