Many recent studies of rhythm and meter have been devoted to the phenomenon of hypermeter and its implication on musical form. Temperley (2008) proposes that the hypermetrical shift between “odd-strong” and “even-strong” hypermeter is often used to emphasize the formal division of a piece. Moreover, Temperley believes that the importance of hypermetrical shift is primarily local, and he would be wary of constructing large-scale analytical narratives involving ‘odd-strong’ and ‘even-strong’ hypermetrical states. However, in my analyses of hypermetrical shift in Haydn’s late Keyboard Trios and String Quartets, I have found some large-scale manipulations of hypermeter that Haydn was consistently applying in his compositions, particularly in his monothematic sonatas. My analyses have shown that the majority of Haydn’s monothematic expositions have an even number of hypermetrical shifts in its transition zone, often starting with the metric reinterpretation pattern and ending with the successive downbeats pattern as a link to the secondary-theme zone. As a result, each formal unit in these monothematic movements is articulated with an altering hypermetrical state, providing tension and momentum to the otherwise predictable monothematic design. Moreover, Haydn seemed to be purposefully associating his thematic materials to a particular hypermetrical state. For his monothematic sonatas, both the primary theme and the secondary theme are usually in the same hypermetrical state; but for the contrasting-theme sonatas, the primary theme is in one hypermetrical state while the secondary theme is in another.