The Fianna Fail Senator raised the issue in the Seanad on Thursday.
There are calls for improvements on the 120 bus route which starts in Edenderry and goes through townlands such as Derrinturn, Newbridge, Allenwood, Kilmeague and into Dublin City Centre.
The issue was highlighted most recently on Kfm's Kildare Today programme by Thomas O' Reilly, a man living in Allenwood who said he has waited numerous times for the bus there, which often doesn't arrive.
Fianna Fail Senator Fiona O’Loughlin has raised the issue in the Seanad on Thursday.
Senator O'Loughlin commented: "I raised specifically the 120 bus route which starts in Edenderry and goes through townlands such as Derrinturn, Newbridge, Allenwood, Kilmeague and on to Dublin.
“The route is completely unreliable. I have been contacted by several commuters who complain of the shoddy service.
"Buses aren't showing up leaving people stranded trying to get to work hospital appointment," she explained.
"Last Thursday morning two buses never showed up, 3 buses on Friday morning never showed.
"Forcing commuters to get taxis or simply miss appointments.
"It is simply not acceptable, and it will deter people from using public transport," she insisted.
Senator O’Loughlin said she welcomed the reduction in public transport fares that were announced recently, and they certainly will make a huge difference to many people.
However, she insisted, "we need to ensure that all services are affordable.
"But we need to see a medium hop zone established to reduce the financial burden on commuters from Newbridge and the surrounding areas also.
“Our public transport system needs to be more extensive and reliable," she added.
The Kildare Senator concluded by saying: “I have managed to get assurances from the NTA that the signage and infrastructure along the route will be upgraded, but I am pushing to try and improve the routes reliability.”