Quests are tasks set for the Dragonborn to perform in The Elder Scrolls V: Dawnguard. In total, there are twenty-two quests featured in the add-on. Twelve are featured in the main quest, with several optional side quests.
The first quest can be started by listening for rumors or asking Hold Guards about a group of vampire hunters who are recruiting. This will steer the Dragonborn in the direction of Fort Dawnguard and the add-on will begin. At level 10, Durak will directly approach the Dragonborn and suggest that they join Dawnguard. Alternately, the questline can be started as early as level 1, by going to Fort Dawnguard via Dayspring Canyon at any time and interacting with the applicants and Dawnguard members.
During the quest "Bloodline," the Dragonborn must decide whether to continue assisting the Dawnguard or join Harkon and the Volkihar Clan. Choosing the path of Harkon opens the Vampire Lord skill tree.
At some point after installing the add-on or starting a new playthrough with it installed, periodic attacks by vampires in the wilderness, as well as on cities and settlements the Dragonborn visits will begin, which can result in the death of various characters, such as merchants, quest givers and other important unprotected characters. To prevent these deaths, it is recommended to reach at least the "Bloodline" quest in the story, after which the attacks will subside.
- Dawnguard – Join the Dawnguard.
- Awakening – Find out what the vampires are seeking.
- Bloodline – Lead Serana to her home and choose who to side with.
- Scroll Scouting – Find three Elder Scrolls to fully decipher the "Tyranny of the Sun."
- Seeking Disclosure – Deliver the Elder Scrolls to Dexion Evicus.
- Chasing Echoes – Gain access to the Soul Cairn.
- Beyond Death – Locate Valerica and her Elder Scroll.
- Unseen Visions – Read the Elder Scrolls at Ancestor Glade.
- Touching the Sky – Obtain Auriel's Bow.
- Kindred Judgment – Confront Harkon in Castle Volkihar.
- Preemptive Strike – Track and kill a Master Vampire before it can turn its followers.
- Ancient Technology – A six-part series of quests which yield Crossbow upgrades.
- Bolstering The Ranks – Recruit Florentius Baenius into the Dawnguard.
- Lost Relic – Locate an ancient dawnguard relic for Florentius.
- Hide and Seek – Kill a vampire disguised as a traveler.
- Cleansing Light – Hunt and kill a leveled vampire.
- Hunting the Monster – Track a Master Vampire to their lair, and kill them.
- A Jarl's Justice – Kill a vampire masquerading as a visiting advisor to a Jarl's court.
- Rescue – Rescue a kidnapped friend of the Dragonborn.
- Rings of Blood Magic – Retrieve the Ring of the Erudite and Ring of the Beast.
- Protecting the Bloodline – Kill the Master Vampire and bandits.
- Deceiving the Herd – Murder a person of stature and frame the Dawnguard by planting a note.
- Ancient Power – Retrieve an Ancient Vampire's body parts.
- New Allegiances – Turn Townspeople into vampires.
- Amulets of Night Power – Retrieve the Amulet of the Gargoyle and the Amulet of Bats.
- Culling the Beast – Kill the Master Vampire and his thralls.
- The Hunt – Kill Dawnguard masquerading as a traveling pilgrim.
- Destroying the Dawnguard – Kill the leaders of the Dawnguard.
- The Gift – Turn a spouse into a vampire.
- Impatience of a Saint – Retrieve ten missing pages of Saint Jiub's Opus.
- Lost to the Ages – Investigate the Dwemer ruin of Arkngthamz.
- Find Arvak's Skull – Search for Arvak's Skull in the Soul Cairn.
- Ancient Falmer Tomes – Bring an Ancient Falmer Tome to Urag gro-Shub.