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* TSX ends down 217.28 points, or 1.1%, at 18,861.36

* For the second quarter, the index loses 13.8%

* Shares of Canopy Growth drop 18.5%

* Air Canada ends 6% lower

TORONTO, June 30 (Reuters) - Canada's main stock index fell on Thursday and posted the biggest quarterly decline since the first quarter of 2020, as rising worries of a global economic slowdown weighed on investor sentiment ahead of a long domestic weekend.

The Toronto Stock Exchange's S&P/TSX composite index ended down 217.28 points, or 1.1%, at 18,861.36, its lowest closing level since last Thursday.

For the month of June, the index fell 9%. It was down 13.8% for the second quarter.

Wall Street also ended lower on Thursday, a dismal coda to the S&P 500's worst first half in more than half a century.

Investors worried that the latest show of central bank determination to tame inflation would slow economic growth.

"I think that fears over recession are continuing to drive sentiment at the moment, driven by central banks continuing to warn that the battle against inflation will likely be a long one," said Stuart Cole, head macro economist at Equiti Capital.

Canada's economy likely contracted 0.2% in May, largely on a drop in oil and gas output, official data showed, while GDP growth in April was in line with analyst forecasts.

Both the technology and energy groups fell 1.7%, with the latter contending with a drop in oil prices. Oil settled 3.7% lower at $105.76 a barrel.

The materials group, which includes precious and base metals miners and fertilizer companies, lost 3.6%.

Shares of Canopy Growth Corp tumbled 18.5%, hitting their lowest level since August 2016, while Air Canada lost 6%. The carrier trimmed its domestic flight schedule this summer, as North American airlines wrestle with labor shortages, delays and cancellations.

The Toronto market will be closed on Friday for the Canada Day holiday. (Reporting by Fergal Smith in Toronto Additional reporting by Amal S in Bengaluru Editing by Matthew Lewis)