* Q2 organic bookings fall 2 pct
* First like-for-like fall in two years
* Q2 earnings narrowly beat expectations (Adds detail, background, analyst comment, updates shares)
By Niklas Pollard and Helena Soderpalm
STOCKHOLM, July 17 Atlas Copco reported its first fall in like-for-like orders since 2009, suggesting that the mining boom the Swedish compressor and machinery manufacturer has been riding for the past two years may be losing steam.
The weakening order book at one of the world's top suppliers of mining gear eclipsed better than expected quarterly earnings and a reassuring forecast for unchanged demand in the near term to send its shares down 2.3 percent to 145.7 Swedish crowns ($20.65) by 1129 GMT on Tuesday.
Atlas Copco and domestic rival Sandvik, both leading producers of mining and construction equipment, have enjoyed years of booming demand from miners.
Activity has also been brisk in other segments, but worries about the global economy have intensified as the euro zone crisis has cast an ever-longer shadow, with signs of weakness beginning to crop up in the United States and Asia.
Atlas said order intake was 23.3 billion crowns in the second quarter, against 22.2 billion crowns a year ago. This fell short of the average forecast of 24 billion crowns in a Reuters poll of 16 analysts and was a 2 percent drop excluding currency swings and acquisitions.
"Ultimately it's the same with a lot of the mechanical names, that order momentum is slowing or going negative and the shares are unlikely to perform in that environment because people's expectations are going to have to come down," Berenberg Bank analyst Alexander Virgo said.
The decline in organic order intake, the first since the end of 2009, was mainly a result of falling demand for mining equipment and large compressors. Atlas's mining operations account for about a third of its revenues.
Operating profit was 5.02 billion Swedish crowns ($711.56 million), against 4.18 billion crowns in the same period last year and an average forecast for 4.81 billion crowns.
Another Swedish company, manufacturing bellwether SKF , jarred the sector last month when it warned of weakening demand and said that the slowdown caused by euro zone debt turmoil had begun spreading to Germany and other key markets.
Swedish engineering group Alfa Laval also saw its stock hit on Tuesday after posting a weaker-than-expected core profit margin for the quarter. ($1 = 7.0550 Swedish crowns)
(Additional reporting by Love Liman; Editing by David Goodman)