Ocean gyre circulations and the associated sea level are experiencing long-term changes due to anthropogenic climate change. Examining these changes between sea level and subsurface dynamic topography and ocean circulation is important for understanding climate change in the oceans. We use regional dynamic height (RDH) with reference to the no-motion layer at 2000 m as a proxy to diagnose ocean circulations and sea level, based on 4 observation-based datasets and 11 Ocean Model Intercomparison Project phase 2 (OMIP-2) model simulations over 1960-2018. The subtropical gyre circulations are identified by the relatively high RDH, which contracts poleward with increasing depths in both hemispheres. North Pacific subtropical gyre circulation only shows positive RDH trends in the upper 400 m with no obvious poleward shift except the Kuroshio and spins down below ~400 m, while the South Pacific subtropical gyre circulation shows positive RDH trends from surface to the no-motion layer and experiences a significant poleward shift. These RDH trends, with asymmetrical distribution between North and South Pacific, are mainly dominated by their thermosteric component, while halosteric component makes a modest contribution only in some region. OMIP-2 simulations can capture the main large-scale changing patterns indicated by observations to some extent, but also show remarkable differences with some regions exhibiting much higher or lower large-scale RDH trends than the observation. The wind stress curl trend drives most changes of dynamic topography and ocean gyre circulations, leading to this asymmetric distribution. Increased stratification in the North Pacific and enhanced ventilation in the South Pacific also contribute to this asymmetric distribution. Continued global warming in the 21^st Century will likely intensify the asymmetric development of subtropical gyre circulations and the associated sea level in the Pacific Ocean.