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This study presents two sets of current records obtained from the South China Sea and satellite altimeter data, and it suggests that near-inertial waves induced by parametric subharmonic instability (PSI) associated with internal tides can be transported poleward beyond their critical latitude phi(c) by background geostrophic flow (BGF). The two mooring locations were poleward of phi(c) (approximate to 14 degrees N) for diurnal subharmonics (0.5D(1); half diurnal frequency D-1); however, both of the current records revealed clear signals at 0.5D(1). The enhanced subinertial motion at 0.5D(1) exhibited a fortnightly spring-neap cycle but did not agree with that of D-1, indicating that it may not be generated via PSI associated with the local D-1. Observations from the altimeter data and a ray-tracing simulation suggested that these nonlocally generated 0.5D(1) waves may be excited near their phi(c), after which they propagated poleward under the role of the BGF to the observation site with a latitude higher than phi(c). The poleward propagation of near-inertial waves can produce elevated vertical shears; thus, it may play an important role in enhancing the local turbulent mixing.