Objective: To observe the influence of lower wide pedicle frontal periosteum flap on frontal bone absorption rate after cranioplasty. Methods: From February 2016 to July 2017, the lower wide pedicle frontal periosteum flap was produced in 12 patients of Shanghai Ninth People′s Hospital (7 males/5 females, aged 5-9 years, 10 hypertelorism, 2 Crouzon syndrome), who accepted intro-cranio-route plastic surgery, to cover the frontal bone window. A spiral CT scans were applied one week (t1) and one year (t2) after surgery. DICOM data was imported into Mimics software to reconstruct the 3D model of skull. The bone window covered the frontal bone was selected and the bone volume was calculated. The absorption rate was calculated as (Vt₁-Vt₂)/Vt₁×100%. As a control group, the CT data of 20 patients (from January 2010 to December 2015, 11 males/9 females, 7 hypertelorism, 12 Crouzon syndrome, 1 Pfeiffer syndrome) were analyzed retrospectively in the same way, and compared to the experimental group. Results: The average bone absorption rate in experimental group was 8.65%±2.56% (n=12), while in control group it was 26.51%±5.23% (n=20). Significant statistical difference was observed. No further cranial defect was observed in one-year follow-up in both two groups. Conclusions The lower wide pedicle frontal periosteum flap reduces the bone absorption rate after intro-cranio-route plastic surgery. It could also help to repair the anterior cranial base defect during the surgery. This technique was recommend as a regular step in craniofacial surgeries.