* Q2 net profit 10.3 mln rials vs 9.1 mln yr-ago
* H1 net profit 19.9 mln rials vs 17.1 mln rials yr-ago
* Assets up 23.3 pct year-on-year, loans up 20 pct (Adds detail, share price)
DUBAI, July 16 (Reuters) - National Bank of Oman, the sultanate's fourth-largest lender by market capitalisation, posted a 13.2 percent rise in second-quarter net profit, edging slightly ahead of analysts' expectations.
The lender made a net profit of 10.3 million rials ($26.8 million) in the three months to June 30, according to Reuters calculations based on a statement to the Muscat stock exchange on Monday, up from 9.1 million rials in the same period of 2011.
Analysts polled by Reuters had estimated an average second quarter profit of 10.1 million rials.
First-half profit at NBO was reported as 19.9 million rials, a 16.4 percent increase from the 17.1 million rials recorded for the same period in 2011.
Loans and advances grew 20 percent year-on-year to 1.86 billion rials at the end of June from 1.55 billion rials at the same point last year.
Total assets stood at 2.49 billion rials at the end of June, a 23.3 percent rise versus 2.02 billion rials at the same point in 2011.
Shares in NBO ended flat on Monday, prior to the disclosure of results, having fallen 8.7 percent year-to-date. This compares to the main Muscat index which has dropped 4 percent in 2012. ($1 = 0.3851 Omani rials) (Reporting by David French; Editing by Dinesh Nair)