The present invention relates to an improvement of an axial turbine. Thereto, the present invention includes a submerged turbine 100 in which a fluid is filled in an interior thereof. The present invention also includes a colliding turbine 200 for ejecting a fluid with a high pressure to rotate blades. The structure of the turbine according to the present invention includes a submerged turbine, a colliding turbine, or a combination type turbine (in which a submerged turbine and a colliding turbine are combined). Accordingly, quality and reliability of the product are significantly improved to satisfy the operator.