Purpose: To evaluate the clinical effect of 5-μm pore filter connected with three-way cock by removing the vehicle in triamcinolone acetonide (TA) suspension.Methods: Through 5-μm pore filter connected with three-way cock, TA suspension was replaced by intraocular irrigating solution. The new suspension has been applied to 60 cases of diabetic branch retinal vein occlusion, diabetic macular edema and agerelated macular degeneration patients through intravitreal injection. It was also been applied to 41 cases of diabetic retinopathy, epimacular membrane, proliferative vitreoretinopathy and idiopathic macular hole patients to assist pas plana vitrectomy (PPV). Whether TA particles can adhere to posterior hyaloid cortex, epiretinal membrane and internal limiting membrane during the surgery have been observed.During follow up, corrected visual acuity and intraocular pressure were recorded.Results: Fiveμm pore filter connected with three-way cock can remove the vehicle in TA suspension successfully and retain TA particles. When the new suspension was applied to assist PPV, it can adhere to posterior hyaloid cortex, epiretinal membrane, internal limiting membrane and visualized them clearly. In all the 41 cases that underwent PPV surgery, visual acuity of 30 cases increased or remained stable.Intraocular hypertension happened in 4 cases. Two cases of the 41 patients had cataract formation during follow up. In the 60 cases that underwent TA intravitreal injection,45 cases increased their visual acuity at least 2 lines. Intraocular hypertension happened in 17 cases and 4 patients had cataract formation. None of the 101 patients caught endophthalmitis or other serious complications.Conclusion: Filter connected with three-way cock can remove the vehicle in TA suspension effectively and this procedure can be applied to intravitreal injection or PPV. This manipulation is so simple that it deserves to be popularized for clinical use.