A Senate committee will look at the purpose, intent and adequacy of the Disability Support Pension, with the expectation of reporting back by the end of November.

The upper house on Thursday agreed to Greens senator Rachel Siewert's motion, putting the inquiry in place.

"There have been a series of changes and cost-saving measures over recent years that have reduced the number of people able to access the Disability Support Program," she said in a statement.

"Since then, there has been a sharp decline in people applying for and being approved for the DSP.

"These changes have also seen a significant increase in sick and disabled people on other payments and having to deal with the JobActive and Disability Employment Services system."

One of the issues senators can look at is whether the payments allow people to maintain an acceptable standard of living in line with community expectations.

The broad terms of reference also includes probing whether the pension can support a disabled person's ability to find long-term, sustainable and appropriate employment.

Australian Associated Press