The Encino Man star has accused Peter Shore of improperly caring for their ill mother Mitzi, who suffers from Parkinson's Disease.
Mitzi has been "rendered susceptible to unscrupulous behaviour and other undue influence because of her condition", according to Shore's lawsuit obtained by RadarOnline.com.
Pauly has also accused his brother of improperly running their business venture, the Comedy Store in Los Angeles, which their mum founded.
The brothers and their mother are the sole directors of the venue, but the actor claims he was "improperly" removed from the board of directors by Peter, the company's chief executive officer.
Pauly is demanding his brother provide tax returns as well as financial reports from the last 36 months in a bid to correct the situation.