Nicole Bricq died in hospital in Poitiers, central France, after falling downstairs on Saturday night.
She is to be buried in nearby La Rochefoucauld, the town where she was born.
Macron paid tribute to her in a tweet that described her as a "free woman", adding, "This committed friend will be greatly missed."
Former president François Hollande hailed a politician who "was able to change her ideas as the world changed".
Joins Socialist Party after 68
Bricq's parents were butchers but she went to university in Bordeaux and went into management.
Inspired by the 1968 students' and workers' revolts, she joined the Socialist Party in 1972, aligning herself with the party's left wing then organised in the Ceres group.
Ceres was led by Jean-Pierre Chévènement, who was to hold several government posts under Socialist president François Mitterrand before forming his own party, the Mouvement des Citoyens, and becoming interior minister under right-wing president Jacques Chirac.
Bricq broke with Chévènement in 1991 because of his opposition to France's participation in the first Gulf War but also differed with him over the European Union, of which she was an ardent supporter while he tended towards a form of left-wing nationalism, opposing the 1992 Maastricht Treaty, for example.
Elected to parliament
The split did her political career no harm.
Having won a seat on the Ile-de-France regional council in 1986, she was elected to the National Assembly in 1997, beating incumbent right-winger Jean-François Copé.
Copé, who was to go on to lead the mainstream right party, have a very public spat with François Fillon and lose to him in a bid to become presidential candidate in 2017, won the seat back in 2002.
Bricq returned to parliament in 2004, this time as a senator for Seine-et-Marne, a seat she kept hold of in 2011.
When Socialist François Hollande won the presidential election the next year, she became ecology minister, but only for a month, her grasp of economics taking her to foreign trade.
Backs Macron presidential bid
She joined his Republic on the Move (LREM) and was named to head the party's slate in Saine-et-Marne in Senate elections later this year.
But she withdrew at the end of last month after Arnaud de Belenet, who had left the mainstream-right Republicans to join Macron's movement, set up another slate that was likely to steal votes from the official LREM one.
Without naming him, Bricq blamed a colleague who had "more ambition than his place on our slate accorded him".
Woman of character
That was an example of a sharp tongue that sometimes made enemies for her.
The trait was responsible for a minor scandal in 2014 when, believing her microphone was switched off, she was caught complaining to then prime minister Jean-Marc Ayrault that the food at the Elysée presidential palace was "disgusting" and that it was not much better at the prime minister's residence.
She shrugged off criticism of her difficult relations with some colleagues.
"If it's a man they say he has character, if it's a woman that she has a bad character," was her comment.
Nicole Bricq: a life in dates
- 10 June 1947: Born in La Rochefoucauld where her parents run a butchers shop;
- 1970: Awarded degree at Montesqieu-Bordeaux IV University;
- 1972: Joins Socialist Party, supporting left-wing Ceres group of Jean-Pierre Chévènement;
- 1983-1989: Regional councillor in Ile-de-France;
- 1991: Breaks with Chévènement over his opposition to France’s participation in first Gulf War;
- 1997: Elected MP for constituency in Seine-et-Marne, east of Paris, unseating right-winger Jean-François Copé;
- 2002: Loses seat to Copé;
- 2004: Elected senator for Seine-et-Marne;
- 2011: First woman to become general rapporteur for the budget in the Senate:
- 2012: Appointed ecology minister after president François Hollande’s election, moved to foreign trade after a month;
- 2014: Loses post in government reshuffle;
- 2017: Supports Emmanuel Macron’s presidential bid, joins Republic on the Move (LREM) party, chosen to head slate in Seine-et-Marne for senatorial election, resigns after internal dissent.
- 6 August 2017: Dies in hospital in Poitiers.