Hello my name is Ronald and my question is do you have to be a great swimmer to join the Marine Corps and if you're not a good swimmer can the Marines teach you or should you learn to swim before you go to boot camp? I would like to join when i turn 18 in october but this is the main issue holding me back. Thank you for your response.

During swim qual week those that do not know how to swim they will teach. I had a few recruits in my platoon that didn't know how to swim. They were givin leasons at that time. All the ones in my platoon qualed and stayed with the platoon. They also teach you the things that they want you to know and need to know in order to qual.
It wouldn't be a bad idea to learn before you ship, but not a necesity.

Since you want to join in October why not take the summer to take lessons at your local YMCA or at times the Red Cross offers swimming lessons.

Like revrnd said, they will teach you but if you want to just do it then try and take lessons so your ready.

rule of thumb is boot camp isn't he place you want to learn somethings. like swimming, push-ups, and pull-ups. train now. it will only help you.