Lord Hunt of Wirral, who is chairman of the PCC, and Ofcom chief executive Ed Richards will talk about how they try to maintain editorial standards.
The inquiry will also hear from Sir Christopher Meyer, who was PCC chairman when News of the World royal editor Clive Goodman was jailed in 2007 for phone-hacking, and Advertising Standards Authority chief executive Guy Parker.
A number of previous witnesses have criticised the self-regulation of newspapers and magazines under the PCC, saying the body does not have enough powers to be effective.
By contrast, Ofcom has wide-ranging powers under the Communications Act 2003 to investigate and penalise breaches of its detailed code - which includes strict clauses on impartiality and privacy - in TV and radio programmes.
The inquiry will hear evidence on Monday from current PCC director Stig Abell and his predecessor Tim Toulmin, who was in the post at the time when Goodman was sent to prison.