Former MTV host Matt Pinfield needs help making decisions on his health and finances after suffering a massive stroke ... at least according to his daughter, who claims she's afraid his girlfriend will drain his bank account.

Matt's daughter, Jessica, beelined it to court and filed for a temporary conservatorship over her father. In the docs, obtained by TMZ, she claims Matt had a stroke three weeks ago and is now incompetent to make health and financial decisions.

In the docs, Jessica says she's concerned about Matt's money and personal property because his girlfriend has access to his accounts ... she and her sister Maya say they are deeply concerned the girlfriend will withdraw Matt's money.

Matt's daughters say he needs temporary conservators to oversee his bank account and apartment.

The MTV legend was practically the face of the network in its heyday, hosting a bunch of MTV shows in the '90s, including "120 Minutes," and dropping some serious music knowledge on 'TRL.'

Matt ultimately got his own TV show and went on to become a vice president of A&R and Artist Development for Columbia Records ... though in recent years he's returned to his roots with a radio gig.

His daughter says Matt suffered the stroke January 6 -- the same day he last posted on Instagram -- and he reportedly had to be hospitalized.