Colette Roy-Laroche was applauded by PQ legislators as she arrived at their evening gathering.
The mayor had won plaudits in Quebec over her response to the devastating July train wreck that killed 47 people and wiped out part of her town.
She is not expected to seek another municipal term.
The official reason for her visit to Quebec City was to brief MNAs on upcoming legislation to delay municipal elections as her town rebuilds.
However, the appearance at a PQ caucus meeting instantly fuelled media speculation that she might be tempted by a future career in provincial politics.
Roy-Laroche was effusive in her praise of the PQ government's response this summer, and especially critical of the railway that operated the train.