With these fruits, the user will become a natural element completely. The users are neither human nor element when they are in their normal state. However, Logia users can turn completely into their element whenever they want to. Logia fruits are the rarest to find in the world of One Piece. Logia users can control their element if it already exists in the environment (ex: Crocodile controlled sand in the desert at his will), but cannot control their elements if the element is in another form (ex: Aokiji cannot control ice if it's in form of water). They may control the element within another form by manipulating the surrounding (ex: Aokiji freezing an ocean, Crocodile turning a field of grass into a desert).
Advantages: Logia users cannot be harmed physically (ex: Luffy's Gomu Gomu attacks had no effect on Smoker). They can also manipulate anything close to their element. For example, through Crocodile's sand powers, he could control dryness and absorb moisture. Another advantage is that Logia users have unlimited amounts of their respective elements and can utilize them from their own bodies.
Disadvantages: There are very few ways of harming logia users. Besides using the sea and seastone, the main method of causing harm to a Logia user are natural weaknesses which, when exploited, can ultimately negate the Logia power. An example of this is when Luffy was able to hit Eneru since his electricity doesn't affect Luffy's rubber body. The only other time a physical blow may hurt the user is when he or she is caught off guard. This can be seen when Luffy flew into a bar in Arabasta and hit both Smoker and Ace through a wall.
- Moku Moku no Mi (Plume Plume Fruit)
Info: This logia type fruit allows the user to turn completely into smoke, create and control smoke. With this ability, the user also makes the smoke hard or soft, which allows him/her to hold onto others.
- Mera Mera no Mi (Flare Flare fruit)
User: Portgas D. Ace
Info: This fruit allows the user to become, create, and control fire at his/her own will.
- Suna Suna no Mi (Sand Sand Fruit)
User: Sir Crocodile
Info: This logia type fruit allows the user to transform into sand and also create and control sand. The user can even dry anything that he/she touches, which can dehydrate living things and turn objects into sand. The weakness to this logia type fruit is that if water comes in contact with the user, he/she becomes vulnerable to attacks and cannot turn back to sand. It is also seen that blood has the same effect as well.
- Goro Goro no Mi (Rumble Rumble Fruit)
User: Eneru (Enel)
Info: This fruit allows the user to transform completely into electricity and create/control it. It also improves Enel's mantra (ability to predict the opponent's movements) as seen in One Piece. The only weakness to this fruit is rubber since electricity cannot affect rubber.
- Hie Hie no Mi (Ice Ice Fruit)
Info: This allows the user to turn completely into ice and also create/control ice. With this ability, the user can freeze an area and actually walk across the surface even on the ocean.
- Toro Toro no Mi* (Liquid Liquid Fruit)
User: Honey Queen
Info: This devil fruit allows the user to transform and control liquid. This ability can only be seen in One Piece Movie 2: Clockwork Island Adventure.
- Ame Ame no Mi* (Syrup Syrup Fruit)
Info: This devil fruit allows the user to transform into candy syrup. Physical attacks are useless against the user that has consumed this fruit. The only weakness is that if the user is covered in flour, then he/she would be vulnerable to attacks. This can only be seen in One Piece Movie 4: Dead End Adventure.