Foreshocks have long been regarded as potential precursors for ensuing mainshocks. Taiwan is frequently struck by large-magnitude earthquakes, but many fundamental foreshock characteristics are poorly understood. In this study, we apply a statistical approach to examine the foreshock activities of ML>5 mainshocks in Taiwan from 2012 to 2022 and to investigate correlations between foreshock and mainshock parameters, with implications for the underlying triggering process. The nearest-neighbor distance method is applied to identify foreshock-mainshock sequences, and we find that approximately a quarter of mainshocks (26%) in Taiwan are preceded by at least one foreshock. While the foreshock occurrence does not correlate with mainshock magnitude, it negatively correlates with mainshock focal depth and rake angle, consistent with observations in inland Japan and California. This indicates that foreshock occurrence is mainly controlled by the normal stress and the abundance of smaller-scale faults in the crust, both of which change with depth. Furthermore, correlations between mainshock magnitude and foreshock parameters—cluster size, spatial extent, and maximum foreshock magnitude—suggest the coexistence of pre-slip and cascade end-member triggering mechanisms in Taiwan. Within the study region, mainshocks occurring along the Ryukyu trench and faults with complex geometry, such as the Longitudinal Valley suture zone, exhibit higher foreshock occurrence than those in Central Taiwan and southeastern offshore regions, as well as correlation between mainshock magnitude and foreshock area, a feature indicative of aseismic slip-driven triggering. Spatial variations in foreshock occurrence may be explained by differences in long-term background seismicity rates and fault architecture.