Abstract: The present invention relates to an aqueous pharmaceutical formulation comprising at least one inhibitor of Rho-associated protein kinase (ROCK). The aqueous pharmaceutical formulation comprises 0.01-0.4% w/v of ROCK inhibitor(s), a non-ionic surfactant in an amount of 0.01-2% w/v, and a tonicity agent to maintain a tonicity between 220-360 mOsm/kG, at a pH between 6.3 to 7.8, wherein the ROCK inhibitor, the surfactant, and the tonicity agent are compatible in the formulation. The aqueous ophthalmic formulations of this invention have an increased ocular bioavailability and/or aqueous humor concentrations without a concomitant increase in systemic concentrations. The present invention further provides a method of reducing intraocular pressure, particularly a method of treating glaucoma, by administering the aqueous pharmaceutical formulation to a subject.