Guto Bebb, MP for Aberconwy in Wales, said Global Restructuring Group (GRG) - the wing of RBS which handles loans classed as risky - sees distressed firms as "opportunities" to make money.
Many companies were told they suddenly had to pay large sums of money for their banking facilities or be forced to accept expensive reviews of their businesses, he said.
There are cases of "systematic bad behaviour" by GRG, the MP said, telling MPs he is concerned there is an "impression of a conflict of interest" by the decision to appoint legal firm Clifford Chance, which previously worked for RBS, to carry out an internal review.
A debate was called in the wake of a report by businessman Lawrence Tomlinson, which alleged that RBS deliberately forced companies into default to seize their properties.
Leading the debate in Westminster Hall, Mr Bebb said that in an interview with finance data firm Debtwire in October last year, the head of GRG, Derek Sach, said he sees struggling businesses as opportunities.
Mr Bebb said: "If the head of GRG is of the view that distressed businesses coming into his organisation are opportunities, then I think we have a view of the world which is not there to support businesses, it is there to try and gain commercial advantage on the back of those individual businesses.
"If there is any MP here today who has business involved in shipping then you should be very concerned because Mr Sach also highlights the fact that he sees significant opportunities in shipping because shipping is currently going through a difficult period.
"In other words, the vultures are hovering within GRG waiting for a further supply of distressed businesses to be taken advantage of.
"If we are serious about supporting small businesses and supporting the growth of our economy through the development of small businesses then we really do have to ask ourselves if this sort of attitude towards small businesses, seeing them as opportunities for money and to make money, rather than as businesses to be supported, is the right way forward."
Treasury Minister Sajid Javid said the Government welcomed the Tomlinson report.
He said: "We take the allegations that are made in that report very seriously and we are pleased the FCA has acted quickly so far to look at those very serious allegations.
"It is important at this stage though to allow the FCA, as the conduct authority, to investigate the claims made in the Tomlinson report."