(Updates with bourse close)

By Alexia Vlahos

SANTIAGO, April 15 (Reuters) - Chilean shares closed slightly weaker on Wednesday, edging back from two-month highs in mixed trade, while the peso closed a shade lower in thin volume, traders said.

The IPSA .IPSA leading share index closed 0.2 percent weaker at 2,640.62 points, preliminary closing data showed, while the all-market IGPA index .IGPA fell 0.11 percent to 12,554.25 points.

"The market closed quite flat. We should remember that we had a very successful week, with a lot of trading done. But today it was a very slow market," said Roberto Guzman, head of investment at the FIT Research brokerage in Santiago.

Chilean stocks posted strong gains earlier this week, after a new central bank interest rate cut on Thursday boosted retail and construction stocks, when commodity shares also posted sharp gains.

By contrast, Wall Street's Dow Jones industrials .DJI closed 1.38 percent firmer as better-than-expected regional factory data lifted hopes that the U.S. recession was moderating, while the Federal Reserve's Beige Book indicated the speed of economic contraction was fading.

Soquimich SQM_pb.SN, Chile's leading exporter of fertilizer and the world's biggest producer of iodine and lithium, closed 0.12 percent higher at 18,320 pesos a share.

Steelmaker CAP CAP.SN fell 2.1 percent to 9,954 pesos, while industrial conglomerate Copec COP.SN, the most heavily weighted share on the bourse, fell 0.22 percent to 5,628 pesos.