* Catalan parliament vote weighs on euro, Spanish IBEX
* Wall Street up on robust earnings, Fed chair report
* U.S. Treasury yields lower (Updates to U.S. open, changes byline and dateline; previously London)
NEW YORK, Oct 27 (Reuters) - The euro held near a three-month low against the U.S. dollar on Friday, undermined by the Catalan parliament's declaration of independence from Spain, while robust corporate earnings reports helped a broad advance in world equity markets.
The Catalan declaration, made after a secret ballot, is now likely to be ruled illegal by Spain's constitutional court.
"Theres no doubt that Catalonia, the issue has been weighing on the euro," said Quincy Krosby, chief market strategist at Prudential Financial in New Jersey.
The euro had its worst day against the dollar in 16 months on Thursday after the European Central Bank said it would cut its bond purchases in half to 30 billion euros a month from January.
"That 1/8the ECB meeting 3/8 was the seminal meeting for the euro for this week," Krosby said. "And then if you couple that with stronger U.S. data, that helps keep the euro weaker."
Stronger-than-expected U.S. third-quarter GDP data helped bolster the dollar. The U.S. economy grew at a three percent annual rate from July to September, showing resilience even as recent storms hurt consumer spending.
The dollar index, which measures the greenback against a basket of major currencies, rose 0.45 percent, with the euro down 0.63 percent to $1.1577.
Gains in the dollar were pared after a Bloomberg report that said U.S. President Donald Trump was leaning toward Federal Reserve Governor Jerome Powell as the next U.S. central bank chairman.
U.S. Treasury note yields turned lower, following the Catalan news and Bloomberg report on Trump's possible Fed chief pick.
Benchmark 10-year notes last rose 9/32 in price to yield 2.4228 percent, from 2.454 percent late on Thursday.
The 30-year bond last rose 16/32 in price to yield 2.9356 percent, from 2.961 percent late on Thursday.
Gold edged higher on Friday, reversing earlier losses after the Catalonian parliament's independence declaration from Spain led investors to seek safety from political upheaval. Spot gold added 0.4 percent to $1,271.14 an ounce.
MSCI's gauge of stocks across the globe gained 0.37 percent.
On Wall Street, gains were led by robust technology earnings and third-quarter GDP growth that lifted investor sentiment.
"Earnings is driving the positive sentiment at the open," said Scott Brown, chief economist at Raymond James in St. Petersburg, Florida. "Certainly a lot of enthusiasm for tech stocks that have reported."
The Dow Jones Industrial Average rose 27.48 points, or 0.12 percent, to 23,428.34, the S&P 500 gained 17.6 points, or 0.69 percent, to 2,578 and the Nasdaq Composite added 117.37 points, or 1.79 percent, to 6,674.14.
Healthy results helped Amazon jump 11.8 percent , while Google-parent Alphabet gained 6.0 percent and Microsoft advanced 7.2 percent . That drove the S&P technology index up about 2 percent. The sector has surged about 30 percent this year, twice the advance in the broader S&P index.
Chevron weighed on the Dow, with its shares dropping 1.9 percent after profit missed estimates.
Spain's IBEX hit session lows after the Catalan parliament declared independence, last dropping 1.5 percent. Europe's STOXX 600 also cut gains after the vote, but remained up 0.6 percent.
The pan-European FTSEurofirst 300 index rose 0.59 percent. European shares hit a five-month high on Friday, helped by strong earnings and the sharp drop in the euro.
MSCI's broadest index of Asia-Pacific shares outside Japan closed 0.18 percent higher, while Japan's Nikkei rose 1.24 percent.
Oil prices rose more 1 percent on support among the world's top producers for extending a deal to cut output and as the dollar retreated from three-month peaks.
U.S. crude rose 2.03 percent to $53.71 per barrel and Brent was last at $60.21, up 1.53 percent on the day.
(Additional reporting by Sruthi Shankar in Bengaluru; Gertrude Chavez-Dreyfuss and Richard Leong in New York; Christopher Johnson and Julia Payne in London; Editing by Bernadette Baum)