Macron's LREM and its ally, the centrist MoDem party, are looking to gain between 400 and 455 seats in the 577-seat National Assembly, far more than the 289 necessary for an absolute majority.
That would give Mr Macron one of the biggest parliamentary majorities seen in 60 years.
The conservative party The Republicans and allied center-right Union of Democrats and Independents held 18.9 percent, the National Front 13.8 percent and the Socialists 7.45 percent.
German Chancellor Angela Merkel congratulated French President Emmanuel Macron on the victory of his party in the first round of parliamentary elections, calling the result a strong vote for reforms.
"Chancellor Merkel: My sincere congratulations to Emmanuel Macron for the great success of his party in the first round. A vote for reforms," tweeted her spokesman Steffen Seibert.
Macron chose Berlin for his first trip abroad as President, holding talks with Chancellor Merkel just days after taking office last month./.