Ghost-type Pokémon are one of the hardest types to find in Pokémon Go, but if you're working your way through the various Research quests for tracking down Mew, you're going to need to find them in bulk.
There are several ways you can find and catch Ghost-types, thankfully, so here on this page we'll run through each and every method for where to find Ghost-type Pokémon as well as giving you a quick Ghost-type Pokémon list of what's available, and note anything else you should bear in mind, too.
Pokémon Go Ghost-types - where to find Ghost-type Pokémon
By far the easiest way to catch Ghost-type Pokémon is by playing the game at night.
Between the hours of around 8pm and 8am local time, peaking at around 2am, Ghost-type Pokémon spawns drastically increase wherever you are, so simply playing the game out and about after dark is going to be your best chance of catching them en masse.
That said, the obvious caveat is that not everyone can, or would like to, be wandering around with their phones out after dark - but thankfully there are a couple of other ways you can rack up those Ghost-Pokémon numbers.
The next is Raids - Duskull, Shuppet, Sableye, Gengar, Misdreavous, Alolan Marowak and Giratina are all still available in Raids at the time of writing, and Sableye in particular is still a fairly regular one to spawn.
You can also solo a Duskull, Shuppet, Misdreavous or Sableye Raid, meaning you don't need to assemble a large squad of friends to help like you would with Gengar, which takes at least three or four players to tackle it comfortably.
There also the added bonus of you increasing your chances of catching a Shiny Shuppet, Sableye or Duskull at their Raids - and Gengar, meanwhile, is a solid competitive option and counter to a few fairly common uses in the current meta, so any of these Raids are useful outside of the fact that they're a source of Ghost-type Pokémon, too.
The downside there of course is that you can only do one Raid a day without having to buy additional Raid passes, and likewise it depends on the luck of the draw with which Raids appear where and when.
Another method is through foggy weather - the in-game weather system boosts the spawn rates of the corresponding types of Pokémon, but typically foggy weather is one of the rarest types (although this of course depends on where you live), so it's not the most reliably way to track the spooky Pokes down.
One more is via conducting certain quests for your Field Research. As part of the January Research rewards, Making 3 Great Throws offers a chance of encountering Gastly, while Sending two Gifts to friends also gives you Gastly.
Of course, make sure the reward is a Mystery Encounter and not an item, otherwise these won't appear!
The final option is finding a Ghost-type nest. Nests, if you didn't know, are specific spots where large numbers of a certain Pokémon will appear - so you might get a lot of Bulbasaur appearing in a certain park for a period of time, for instance, until the nests change.
They rotate fairly often, so if you find one be sure to take advantage of it quickly. To find out what nests are near you, pop your location into The Silph Road's handy nest locator, here.
A few new exciting additions are coming to the game - Armored Mewtwo, an on-going series of Pokémon Go Global Challenges, the tease of Shadow Pokémon and the Invasion of Team Go Rocket. In the meantime, we have a new Go Fest Global research task rewards and the Jump-Start Research quest and Field Research, which can help with some of the harder-to-find Gen 4 Pokémon. The release of Gen 5 Pokémon has also been hinted at! Elsewhere, you can read up on the latest the currently available Legendary Pokémon.
Pokémon Go Ghost-type Pokémon list
The other main thing it helps to know is what Ghost-type Pokémon there are in Pokémon Go at the present time. Here's a list of Ghost-types available now:
Gastly, Misdreavus, Sableye, Shuppet and Duskull are the ones you're most likely to encounter, particularly at night, with the others all second or third-stage evolutions, or more unique Pokémon, and are therefore much rarer to find in the wild.
Keep an eye out then, and do be safe if you're playing at night!