【Abstract】 Objective To investigate the effects of fenestration and decompression technique combined with negative pressure suction on prognosis of patients with odontogenic jaw cystic lesions. Methods According to the random double blind method, 40 patients with odontogenic jaw cystic lesions treated in our hospital were divided into control group and observation group with 20 cases in each. The control group was treated with simple fenestration and decompression, while the observation group was treated with fenestration and decompression combined with negative pressure suction. The improvement of facial contour after treatment, treatment course, curative effect, cystic cavity volume before and after treatment, the rate of decreased cystic cavity volume after treatment, rate of decreased cystic cavity area and followup recurrence rate were compared between the two groups. Results 1 months after the treatment, lower lip numbness in the two groups recovered. The treatment course of observation group (52±05 months) was significantly shorter than that of control group (86±08 months) (P＜0001). There was significant difference between cyst volume of observation group and control group (P＜0001). The rates of cyst volume decrease and cyst area decrease (857±27% and 851±68%) were higher than that of control group (639±56%、 and 630±55%) (P＜0001). The total effective rate of the two groups was not different (P＞005). Conclusion Fenestration and decompression combined with negative pressure suction can significantly shorten the treatment course. Compared with simple decompression, fenestration and decompression combined with negative pressure suction has significant effects in treatment of odontogenic jaw cystic lesions and the recurrence rate is low.