Turnover totalled 4.19 billion shares valued at 1.48 billion pesos (26.86 million dollars) from 5.48 billion shares worth 1.83 billion pesos on Friday.
The broader all-shares index fell 4.74 points to 1,158.49.
Losers beat gainers 62 to 41, with 39 stocks unchanged.
The market enjoyed some support after the government said before trading began that the economy grew 6.1 percent in 2004, said Lawrence de Leon of Accord Capital Equities.It was the fastest pace for annual economic growth since 1996, when gross domestic product expanded 5.8 percent.
"The growth rate was within expectations, but the market is happy with a healthy gain for the economy despite high oil prices and rising inflation," he said.
"Sentiment was mixed, with investors pocketing gains in mining and other stocks, and buying into select blue chips," he added.
However, dealers said the market was ripe for profit-taking after sharp gains at the end of last week, which took the key index back above 2,000 points and many stocks to overbought levels.
Ayala Land Inc was the most actively traded stock, but remained unchanged at 9.10 pesos.
Philippine Long Distance Telephone Co (PLDT) fell five pesos to 1,425 pesos in line with its New York-listed American Depositary Receipts, which retreated 23 US cents to 26.03 US dollars on Friday.
Metropolitan Bank and Trust Co rose one peso to 32.50 pesos.
Ayala Corp was up 20 centavos at 7.90 pesos and Metro Pacific gained one centavo at 52 centavos.
Bank of the Philippine Islands advanced 50 centavos to 58.50 pesos.
Globe Telecom fell 10 pesos at 925 pesos ahead of its 2004 results.
Food and beverage giant San Miguel Corp saw its B shares, available to foreign investors, rise 50 centavos to 78 pesos, but its A shares were unchanged at 58 pesos.