Purpose — to evaluate the efficiency of modified crosslinking (M-CXL) in the treatment of purulent keratitis (PK) and corneal ulcers, including ulcers of mixed etiology. Material and methods. M-CXL method involves simultaneous performance of CXL and frequent instillations of anti-infective agents (one drop every 5 minutes for 1 hour). The study included 39 patients (41 eyes) with purulent corneal ulcers (PCU) of various origin. The main group consisted of 26 patients (27 eyes) who were treated with M-CXL in combination with active conservative therapy. In the control group (13 patients, 14 eyes) only active conservative management was used. Results. Complete suppression of the purulent process in the main group was achieved in 21 (77.8%) eyes after 32.6±10.66 days, in the control group — in 9 (64.3%) eyes in 52.4±16.6 days. Complete suppression of purulent keratitis was achieved in 100% of cases with bacterial keratitis, 83% of cases with fungal keratitis and 70.5% of cases with mixed keratitis. When purulent infiltration occupied the entire depth of the stroma but was limited in area (less than 6 mm), the efficiency of M-CXL decreased to 66.6%. The clinical effect of M-CXL was absent or insufficient when PK extended to the Descemet’s membrane with an area of more than 7 mm. Conclusion. In 77.8% of cases, modified crosslinking has showed pronounced therapeutic effect — complete arrest of purulent corneal infiltration. Recovery time in the main group was 1.6 times shorter than in the control group (p<0.05). Resorption of the purulent infiltration occupying all layers of the stroma up to the Descemet’s membrane with extensive areas was not achieved, however the corneal melting and keratitis progression were stopped, which allowed planned therapeutic penetrating keratoplasty with a graft of smaller diameter to be performed.