MP Katarzyna Kotula outlined the group's social policy plans in an interview with the state news agency PAP on Wednesday.
"All the existing family-friendly programmes should be maintained," she said.
Kotula, a prominent lawmaker with the Left group, added that the new government should increase the new disability benefit, which will be available to adults with disabilities from January 1.
She said there should be "urgent talks about legal changes" to expand this measure "in line with the needs of people with disabilities."
Left-wing lawmakers will also seek to secure measures to support personal assistants for people with disabilities, and parents of children with disabilities, Kotula told PAP.
She added that a new government including her group would also take steps to "de-institutionalise foster care" and introduce support for elderly carers, the PAP news agency reported.
Another goal will be to "mitigate demographic change" by helping mothers return to work, funding in vitro fertilisation and pursuing "an effective migration policy," Kotula stated.
Poles elected a new set of 460 MPs and 100 senators when they went to the ballot box last month.
Polish President Andrzej Duda on Monday named outgoing Prime Minister Mateusz Morawiecki as prime minister-designate, tasking him with forming a new Cabinet.
Morawiecki's conservative Law and Justice (PiS) party won Poland's October 15 election, but lost its parliamentary majority and looks unlikely to stay in power for a third consecutive term.
A bloc of pro-EU opposition parties, including the Left, on Monday secured a resounding victory in Poland's new parliament during its first key vote to elect a house Speaker.
Poland's pro-European opposition groups last Friday signed an agreement to form a coalition government, pledging to restore the rule of law, promote green energy and relax abortion rules, among other policies.
(pm/gs)
Source: PAP