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AH Her is a Z Cam-type dwarf nova with an orbital period of ~ 0.258 d. Dwarfnova oscillations and long-period dwarf nova oscillations have been detected,but no quasi-periodic oscillations (QPOs) and negative superhumps (NSHs) havebeen found. We investigated the association between NSHs, QPOs, and outburstsof AH Her based on \textit{TESS} photometry. We find for the first time theNSHs with a period of 0.24497(1) d in AH Her, and trace the variation of theamplitude and period of NSHs with the outburst. The amplitude of the NSHs ismost significant at quiescence, weakening as the outburst rises, becomingundetectable at the top, rebounding and weakening at the plateau, andstrengthening again as the outburst declines. The variation of the accretiondisk radius can explain the NSHs amplitude variation except for the plateau, sowe suggest that the relationship between NSHs amplitude and outburst can beused as a window to study the accretion disk instability and the origin ofNSHs. In addition, we find the periodic variations in the amplitude, maxima,and shape of the NSHs ranging from 2.33(2) d to 2.68(5) d, which may be relatedto the precession of the tilted disk. Finally, we find QPOs at the top of AHHer's long outburst with ~ 2800 s similar to HS 2325+8205, suggesting that thepresence of QPOs at the top of Z Cam's long outburst may be a generalphenomenon

Evolution of negative superhumps, quasi-periodic oscillations and outbursts in the Z Cam-type dwarf nova AH Her