The B KVV and Cl LVV normal and resonance Auger electron spectra in gaseous BCl3 have been observed with use of tunable photon beam from synchrotron radiation. The spectrum excited by photons with energy above the B K and the Cl L(2,3) thresholds shows preferentially Cl LVV normal Auger bands. The pure B KVV normal Auger spectrum is obtained using the photons with energy between the B K threshold and the Cl L pre-edge excitation threshold. The spectator and participant Anger processes are observed at the B 1s --> 2a(2)''(2p pi(B)) and 1s --> 4e'(sigma(BCl)*) resonances. The spectator Auger processes are also observed in the Cl L(2,3) excitation region, while the participant Auger processes are not significant in this region. The observed spectra are discussed with the aid of the one-electron properties of the valence orbitals.