This is a list of diffuse nebulae. Most nebulae are diffuse, meaning that they do not have well-defined boundaries. Types of diffuse nebulae include emission nebulae and reflection nebulae.
Emission and reflection nebulae
- Barnard's Loop
- Barnard's Merope Nebula
- Bernes 149
- Boomerang Nebula
- Bubble Nebula, NGC 7635
- Bubble Nebula in Barnard's Galaxy
- California Nebula
- Carina Nebula
- Cave Nebula
- Corona Australis Molecular Cloud
- Cone Nebula
- Crescent Nebula
- Double Helix Nebula
- Eagle Nebula
- Elephant's Trunk Nebula
- Eta Carinae Nebula
- Flame Nebula
- Fish Head Nebula
- Fly Nebula
- Gum Nebula
- Gabriela Mistral Nebula
- Heart Nebula
- Homunculus Nebula
- Horsehead Nebula
- Hubble's Variable Nebula
- Iris Nebula
- Lagoon Nebula
- North America Nebula
- Omega Nebula
- Orion Nebula
- Pistol Nebula
- Rosette Nebula
- Running Chicken Nebula
- Soul Nebula
- Tarantula Nebula
- Trifid Nebula
- Witch Head Nebula
- Messier 43
- Messier 78, reflection nebula
- NGC 248
- NGC 249
- NGC 256
- NGC 261
- NGC 267
- NGC 281, Pacman Nebula
- NGC 346
- NGC 371
- NGC 588
- NGC 595
- NGC 604
- NGC 1435, reflection nebula in the Pleiades
- NGC 1491
- NGC 1579
- NGC 1714, NGC 1715
- NGC 1788, reflection nebula in Orion
- NGC 1931
- NGC 1973, NGC 1975 and NGC 1977
- NGC 1999, reflection nebula in Orion
- NGC 2014
- NGC 2023
- NGC 2080, Ghost Head Nebula
- NGC 2174
- NGC 2261, variable reflection nebula in Monoceros
- NGC 2736, the Pencil Nebula
- NGC 3576
- NGC 3603
- NGC 6188
- NGC 6193, open cluster with nebulosity in Ara
- NGC 6334
- NGC 6357
- NGC 6559
- NGC 6589, reflection nebula in Sagittarius near NGC 6590 and I 1284
- NGC 6590, reflection nebula
- NGC 6914
- NGC 7129, reflection nebula in Cepheus, near the open cluster NGC 7142
- LBN 7
- LBN 140
- LBN 179
- LBN 206
- LBN 330
- LBN 357
- LBN 437
- LBN 777
- LBN 1235
- LBN 084.24-07.79
- LHA 120-N55
- vdB1
- vdB 12
- vdB 13
- vdB 14
- vdB 15
- vdB 16
- vdB 38
- IC 349, small reflection nebula in the Pleiades
- IC 2177
- IC 2631, reflection nebula in Chamaeleon
- IC 4604
- IC 4605
- IC 5146
- Sharpless 2-1
- Sharpless 2-112
- Sharpless 2-157
- Sharpless 2-235
- Sharpless 2-263
- Sharpless 2-297
- N41
- DWB 20
- DWB 169
- DWB 175