GSOC has been granted permission to hire four more investigators and a support staff member to deal with its growing workload.
The commission, responsible for dealing with incidents involving Gardaí, said it has seen a surge in whistleblower disclosures since the start of this year.
It said despite a strengthening of the legislation governing its role in recent years, it has not yet been given the resources to deal with it.
The commission said in a statement: "The 2014 Act promised more structure and protections than previously provided to gardaí and their civilian colleagues in An Garda Síochána.
"In passing the 2014 Act there appears to have been no regard for the provisions of Part 4 of the Garda Síochána Act 2005 and this has led to investigative complexities which have been challenging to reconcile.
"Following from the 2014 Act, GSOC began receiving disclosures under the Protected Disclosures Act 2014. In early 2017 in particular we saw an increase in such disclosures."
They said that so far there have been 24 disclosures under the 2014 Act made to them since 2014.
GSOC said: "In the almost three years since the legislation was passed GSOC has not received any additional personnel or accompanying resources to carry out the necessary investigations. GSOC has had to 'add on' this important work to an already congested workload.
"The allocation of five staff members is welcomed by GSOC and the steps are already underway to fill the posts."
GSOC said it will pursue the Tánaiste commitment to address the shortfall in this Autumn's budget.