Motor Oil Q1 net falls 49.9 pct on refining margins

* Net profit slightly above analyst forecast

* EBITDA down 39.9 pct to 42.25 million euros

ATHENS, May 27 (Reuters) - Greece's second-largest refiner Motor Oil Hellas (MORr.AT: Quote, Profile, Research) said on Wednesday its first quarter net profit fell nearly 50 percent year-on-year to 19.23 million euros ($26.81 million), hurt by narrower refining margins.

The profit, which declined from 38.4 million euros in the year-ago period, was slightly above analysts' average forecast of 18.7 million.

The company's earnings before interest, tax, depreciation and amortization (EBITDA) declined 39.9 percent to 44.25 million euros in the first quarter, slightly below analysts' average forecast of 45.3 million euros.

Motor Oil shares trade at 10 times estimated 2009 earnings, compared with about 12 for Hellenic Petroleum, Greece's top refiner, data from Reuters estimates showed.

Motor Oil's share price has gained about 13.5 percent since the start of the year, underperforming a 25 percent advance in the Athens benchmark index .

Hellenic Petroleum (HEPr.AT: Quote, Profile, Research) said last week its first-quarter net profit fell 63 percent year-on-year to 34 million euros as falling oil prices reduced its inventory value.

(Reporting by Ingrid Melander and Angeliki Koutantou; Additional reporting by Harry Papachristou, editing by David Cowell)