Cavitation　plays　important　roles　in　almost　all　high-intensity　focused　ultrasound　(HIFU)　applications.　However,　current　two-dimensional　(2D)　cavitation　mapping　could　only　provide　cavitation　activity　in　one　plane.　This　study　proposed　a　three-dimensional　(3D)　ultrasound　plane-by-plane　active　cavitation　mapping　(3D-UPACM)　for　HIFU　in　free　field　and　pulsatile　flow.　The　acquisition　of　channel-domain　raw　radio-frequency　(RF)　data　in　3D　space　was　performed　by　sequential　plane-by-plane　2D　ultrafast　active　cavitation　mapping.　Between　two　adjacent　unit　locations,　there　was　a　waiting　time　to　make　cavitation　nuclei　distribution　of　the　liquid　back　to　the　original　state.　The　3D　cavitation　map　equivalent　to　the　one　detected　at　one　time　and　over　the　entire　volume　could　be　reconstructed　by　Marching　Cube　algorithm.　Minimum　variance　(MV)　adaptive　beamforming　was　combined　with　coherence　factor　(CF)　weighting　(MVCF)　or　compressive　sensing　(CS)　method　(MVCS)　to　process　the　raw　RF　data　for　improved　beamforming　or　more　rapid　data　processing.　The　feasibility　of　3D-UPACM　was　demonstrated　in　tap-water　and　a　phantom　vessel　with　pulsatile　flow.　The　time　interval　between　temporal　evolutions　of　cavitation　bubble　cloud　could　be　several　microseconds.　MVCF　beamformer　had　a　signal-to-noise　ratio　(SNR)　at　14.17　dB　higher,　lateral　and　axial　resolution　at　2.88　times　and　1.88　times,　respectively,　which　were　compared　with　those　of　B-mode　active　cavitation　mapping.　MVCS　beamformer　had　only　14.94%　time　penalty　of　that　of　MVCF　beamformer.　This　3D-UPACM　technique　employs　the　linear　array　of　a　current　ultrasound　diagnosis　system　rather　than　a　2D　array　transducer　to　decrease　the　cost　of　the　instrument.　Moreover,　although　the　application　is　limited　by　the　requirement　for　a　gassy　fluid　medium　or　a　constant　supply　of　new　cavitation　nuclei　that　allows　replenishment　of　nuclei　between　HIFU　exposures,　this　technique　may　exhibit　a　useful　tool　in　3D　cavitation　mapping　for　HIFU　with　high　speed,　precision　and　resolution,　especially　in　a　laboratory　environment　where　more　careful　analysis　may　be　required　under　controlled　conditions.　(C)　2016　Elsevier　B.V.　All　rights　reserved.