Astrometric study of the T Tauri stars (TTS) candidates and non-TTS X-ray sources around Tau-Aur [Li, Hu 132 (1998) 173], based on the Hipparcos and the ACT Reference Catalogue, is presented in this paper. The ROSAT selected X-ray sources are found to have complicated nature. A few of them are associated with the Tau-Aur or the Orion Star Forming Regions (SFR). Some, with distances similar to that of Tau-Aur but indicating discrepant proper motions, are probable or solid Pleiades supercluster members and other late type young active stars of unresolved nature, the latter are more likely formed in rapidly moving cloudlets, or else have originated from different sites rather than Tau-Aur and dispersed to the present locations. A number of the non-TTS X-ray sources studied are possible Hyades cluster members. Some TTS candidates could be foreground pre-main sequence stars or actually young dwarfs not yet depleted their Lithium.