Shares of Power, Refinery, Auto, Capital Goods and PSU declined due to heavy selling pressure from investors.
However, shares of IT and Tech firmed up on good demand from investors due to weakness of rupee against the dollar.
Tepid monsoon forecast and slowdown in buying by foreign funds, who have been major buyers on the domestic bourses, have dampened sentiments, brokers said.
Rising tension in Iraq which drove oil prices to 9-month high and increase in wholesale inflation weighed on stocks.
Costlier crude is a double whammy for the Indian economy, which imports 80 per cent of oil supplies, as trade gap widens and threatens to push inflation higher. This will reduce room for RBI to lower lending rates in a bid to boost growth.
The Sensex resumed slightly higher at 25,239.50 and firmed up further to a high of 25,609.28 on initial strong buying. But declined afterwards to 25,056.18 before settling the week at 25,105.51, disclosing a loss of 122.66 points or 0.49 per cent.
It has lost 290.95 points or 1.15 per cent in two weeks.
The NSE 50-share Nifty also dropped by 30.65 points, or 0.41 per cent, to 7,511.45.
"Concern over higher crude oil and rupee depreciation has dampened market sentiment. Inflation has also come on higher side which leave lower hopes for rate cut in near term," said Nidhi Saraswat, Senior Research Analyst, Bonanza Portfolio.
The Wholesale Price Index-based inflation accelerated to 6.01 per cent in May from 5.20 per cent in April.
Meanwhile, foreign portfolio investors (FPIs) sold shares worth a net Rs 405.67 crores during the week as per the Sebi's record, including the provisional figure of June 20.
Among the 30-share sensex, 17 fell and 13 firmed up.
Major losers were Mahindra & Mahindra Ltd (7.12 per cent), Reliance Industries (RIL) (4.08 per cent), Hero Motocorp (2.66 per cent), Larsen (2.31 per cent), Tata Power (2.17 per cent), ICICI Bank (2.15 per cent), HUL (1.64 per cent), Maruti Suzuki (1.60 per cent), HDFC Bank (1.25 per cent), NTPC (1.14 per cent), Tata Steel (1.14 per cent) and ONGC (1.12 per cent).
However, Gail India rose by 5.42 per cent, Infosys 4.21 per cent, TCS 3.24 per cent, Axis Bank 2.53 per cent, Cipla 2.51 per cent, Bharti Airtel 1.88 per cent and Wipro 1.39 per cent.
Among the S&P BSE sectoral indices, Power fell by 9.68 per cent followed by Oil&Gas 2.18 per cent, Auto 2.08 per cent, CG 1.61 per cent, PSU 0.89 per cent, Metal 0.71 per cent and Bankex 0.65 per cent.
However, CD rose by 4.41 per cent, IT by 2.84 per cent and Teck by 2.69 per cent.
Total market turnover on the BSE and the NSE dropped to Rs 18,443.21 crore and Rs 91,243.12 crore, respectively from the last weekend's level of Rs 23,388.26 crore and Rs 1,15,538.14 crore.