The　H-atom　abstractions　of　benzaldehyde　by　H/Ö/OH/CH3/HO2/O2　are　calculated　by　the　RRKM-Master　Equation　at　CCSD(T)/cc-pVTZ//M06-2X/6-311+g(d,　p)level　to　predict　reaction　rate　coefficients.　The　calculated　rate　coefficients　of　benzaldehyde　+OH　are　generally　in　good　agreement　with　literature　measurements.　A　random　sampling　method　is　used　to　estimate　the　global　uncertainty.　A　comparison　between　benzaldehyde　and　acetaldehyde　reveals　that　their　rate　coefficients　are　consistent　only　in　H-abstractions　by　H　and　HO2,　but　conflictive　in　other　reactions,　especially　in　the　case　of　OH　attacking.　This　study　theoretically　proves　the　unreasonableness　of　direct　analogy　of　H-atom　abstraction　reactions　of　benzaldehyde　from　acetaldehyde.　©　2022,　Journal　Press　of　Tianjin　University.　All　right　reserved.