Objective To explore the morphometric features of the foramen venosum (FV) and highlight the anatomical type. Methods A total of 82 adult skull specimen with a complete sphenoid bone were examined with a sliding caliper. Diameters of the FV

distance between the FV and foramen ovale (FV-FO)

and distance between the FV and formen spinosum (FV-FS) were measured in an intracranial view of the skull. Results The FV was identified in 31 skulls and bilaterally occurred in 13 skulls.Diameter of the left FV

FV-FO and FV-FS were (1.46±1.03)mm

(2.42±0.87)mm and (10.74±1.18)mm respectively. Diameter of the right FV

FV-FO and FV-FS were (1.60±0.94)mm

(2.34±1.15)mm and (10.40±1.21)mm respectively.There was a negative correlation between the diameter of the FV and FV-FS in the left side (P=0.025

r=-0.597). Both the left and the right side showed a positive correlation between FV-FO and FV-FS. Conclusion FV is closely related to the structure of the foramen ovale and the foramen spinosum.The information provided with this study can help the surgeons and researchers to increase the understanding about the anatomy in the middle cranial fossa

improve the success rate of operation

and reduce complications.