Either can. Theoretically the student fills it out, but the form asks for a lot of parental financial information, which quite frankly I had no intention of sharing with 18 year old kids, so I filled out the FAFSA forms. After they got a little older, I involved them more in the process.You can also have your financial advisor (a third party) fill out the FAFSA - there is a place in the form to specify who is actually providing the information. The online form is easy to use (has become much easier over the past ten years, actually) but it helps to have all the required data assembled before you begin: social security numbers, drivers' license information, and the previous year's IRS form 1040.You can also automatically copy most of the information directly over into a second FAFSA form, which saves a huge amount of time if you have more than one kid.It takes roughly an hour - maybe a little longer the first time you go through it, but it isn't all that difficult.Be aware though, that the EFC reported after you fill out the FAFSA (the 'expected family contribution') is stupid high. But don't worry - colleges know that. They just use the FAFSA along with other information to 'place' the students in their system - I haven't had any college actually expect us to come up with the crazy EFC amounts.So don't freak out - it is just a number, not what you will actually be expected to pay.(thank goodness)Encourage your child to get a job and pay as much toward college as they can manage, though.