Danny O'Donovan claims he began working with the musical siblings in July, 2016 to serve as the tour manager for Janet's State of the World Tour, for which he reportedly agreed to be paid a monthly fee of $25,000 (£19,800).
In court documents obtained by TMZ, he states that the funds stopped rolling in five months into the gig, but despite the purported lack of payment, he remained in the job for a total of 17 months.
The trek, which began in September, 2017, wrapped in October.
It's not clear why O'Donovan didn't take action to collect on the allegedly outstanding fees sooner, but he is now suing for a total of $300,000 (£237,000).
Representatives for Janet and Randy Jackson have yet to comment on the lawsuit.