The size and weight of a Maine coon, especially a fully grown male, can be pretty intimidating. If you have ever seen inside their mouths, they have pretty big teeth, too. If you are someone who has been unfortunate enough to be on the wrong side of a normal-sized domestic cat, you will know that they can hurt you. Add that fear to the size and weight of a Maine coon, you will probably be asking yourself, are they aggressive? The reality is pretty simple; most pet species are only as aggressive as they are brought up to be.
You can have the friendliest big dog or the most aggressive mouse, and the same goes for Maine coon cats. However, as a general temperament, they are very relaxed animals, with a friendly personality. Most times, you can pick them up without any worry that they will scratch or bite you at all. However, of course, there are some exceptions. Catching a Maine coon off guard by picking them up from behind when they have no idea that you are there may invoke a reaction. So, treat them well, and be nice to them, and they are not aggressive at all.