It had posted net profit of Rs 554.56 crore for the same period of last fiscal, 2012-13.
However, the total income in Q2, 2013-14 increased to Rs 7,882.29 crore, from Rs 6,655.66 crore in the year-ago period.
The provision and contingencies of the bank rose to Rs 936.75 crore as compared to Rs 487.09 crore in the same period a year ago, Union Bank of India said in a filing to the BSE.
During the first half of the current fiscal, the bank's net profit also slipped by 28 per cent at Rs 768.34 crore, as against Rs 1,066.15 crore in H1, 2012-13.
The total income rose to Rs 15,495.82 crore in the first six months from Rs 13,216.76 crore in the year-ago period.
As of September 30, 2013, gross non-performing assets (NPAs) of the bank was 3.64 per cent of gross advances, as against 3.66 per cent year a year ago.
Its net non-performing assets during Q2, 2013-14 rose from 2.15 per cent from 2.06 per cent.