The invention relates to a cylindrical annular slit throttling ratio adjustable throttler which comprises a throttler installation body, a throttler installation sleeve and a throttler body, wherein the throttler installation sleeve is arranged in the throttler installation body; the throttler body is arranged in the throttler installation sleeve; a gap positioned between the cylindrical rear end part of the throttler body and the columnar rear end cavity body of the throttler installation sleeve forms a throttler working area; the front end part of the throttler body is provided with a through hole communicated with the throttler working area; a spring is arranged between the front end part of the throttler body and the second hole shoulder of the throttler installation sleeve; the position of the rear end part of the throttler body, which is positioned on the second rear end cavity body of the throttler installation sleeve, can be adjusted by adjusting a pressure head so that the throttling ratio is adjusted. The integral static pressure support system can use the throttler with single size form and meets the requirements on the characteristics of excellent property, compact structure, convenience in disassembly and assembly, difficulty in blockage, and the like.