<p>The present invention provides an intravenous fluid flow regulator (10) for controlling the I.V. administration of medical fluid to a patient. The fluid flow regulator (10) provides a housing (12) having a top (18) and a bottom (20). A flexible diaphragm (14) is positioned within housing (12). A diaphragm holder (16) is provided inside housing (12) for holding a sealing edge (56) of flexible diaphragm (14) in fluid sealing engagement with diaphragm holder (16). The housing (12) and flexible diaphragm (14) define an inlet fluid reservoir (62) and an outlet fluid reservoir (64). The diaphragm holder (16) defines a by-pass fluid channel (54) from inlet fluid reservoir (62), around diaphragm (14), to outlet fluid reservoir (64). The flexible diaphragm (14) being flexible to alternatively move into inlet fluid reservoir (62) and outlet fluid reservoir (64) depending on a fluid pressure differential between inlet fluid reservoir (62) and outlet fluid reservoir (64).</p>