The Sensex, which commenced on a cheerful note, spurted by 294.71 points to 17,046.44 at 1245 hrs, a level last seen on 14th November, last year.
Similarly, the broad-based National Stock Exchange index Nifty crossed 5,100 mark levels by adding 94.80 points to 5,141.05 at the same time.
The upsurge was led by capital goods, banking, realty and metal stocks.
Engineering major Larsen and Toubro rose by 5 per cent, while banking giant State Bank of India by 4.76 per cent. Private lender ICICI Bank gained 3.46 per cent.
Trading sentiment bolstered as the Reserve Bank of India cut cash reserve ratio (CRR) by 0.50 percentage point to 5.5 per cent for the first time since 2009 and signaled future interest-rate cuts in its monetary policy review.