BEIJING, July 18 (Reuters) - Chinese leaders pledged on Thursday to modernize the country's industrial complex, expand domestic demand, curb debt and property sector risks, as well as implement financial and fiscal reforms, state media said after a key Communist Party meeting.

The official news agency Xinhua's readout of the meeting, which takes place roughly every five years, also said Beijing wanted to improve social security, healthcare and income distribution systems and introduce land reforms.

The report said China will "enhance the role of market mechanisms in the economy, create a fairer and more dynamic market environment and optimize the efficiency of resource allocation."

The previous wording in official documents was that markets would "play a decisive role" in the economy.

"Restrictions on the market will be lifted, while effective regulation will be ensured to better maintain order in the market and remedy market failures," said the report.

The meeting readout did not say what changes will be implemented, but said the "tasks" should be completed by 2029.

A document with more detailed policy plans presented at the four-day, closed-door meeting of Communist Party central committee members led by President Xi Jinping, is expected to be released in coming days.

Previewed by state media as "epoch-making," the event, known as a plenum, took place at a time of financial hardship for an increasing number of Chinese at home and of heightened adversity against the country's industrial policies abroad. (Reporting by Beijing newsroom Editing by Peter Graff and Susan Fenton)