The molecular formula C₃H₆O may refer to:

• Alcohols
  • Allyl alcohol or 2-propen-1-ol, CH₂=CH-CH₂OH, CAS number 107-18-6
  • cyclopropanol or cyclopropyl alcohol, cyclo (-CH₂-CH₂-HOHC-), CAS number 16545-68-9
• Aldehydes
  • propanal or propionaldehyde, CH₃CH₂-CHO, CAS number 123-38-6
• Ketones
  • Propanone or acetone, CH₃-CO-CH₃, CAS number 67-64-1
• Enols (tautomers of aldehydes and ketones)
  • (E)-1-propen-1-ol, CH₃-CH=CH-OH, CAS number 57642-95-2
  • (Z)-1-propen-1-ol, CH₃-CH=CH-OH, CAS number 57642-96-3
  • propen-2-ol, CH₂=C(OH)-CH₃, CAS number 29456-04-0 or 74324-85-9
• Ethers
  • methyl vinyl ether or methoxyethene, H₃C-O-CH=CH₂, CAS number: 107-25-5
  • oxetane or trimethylene oxide, cyclo(-CH₂-CH₂-O-CH₂-), CAS number: 503-30-0
  • 1,2-epoxy-propane or Propylene oxide or methyl oxirane, cyclo(-C*H(CH₃)-CH₂-O-), C* chiral, CAS number: 75-56-9
    • (R)-(+)-methyl oxirane, CAS number 15448-47-2
    • (S)-(–)-methyl oxirane, CAS number 16088-62-3