The flag field is navy blue with all lettering and symbols in gold, representing the state colors of Oregon. On the obverse, the legend STATE OF OREGON is written above an escutcheon, which also appears in the Oregon state seal. The shield is surrounded by 33 stars, representing Oregon's admission to the Union as the 33rd state. Below the shield is written 1859, the year in which Oregon became a state.

Oregon's flag is the last remaining state flag in the U.S. in which the obverse and reverse sides have different designs. Paraguay is the only country that still has a two-sided flag. Two-sided flags were previously more common, but have been reduced due to increased costs of manufacturing a flag with two different designs. On the reverse of the flag is a depiction, also in gold, of a beaver, the state animal of Oregon. Oregon has the only U.S. state flag with differing symbolism on two sides.

For dress or parade usage, the flag may feature a gold fringe. For standard usage, no fringe is required. The ratio of the flag's width to length is 3:5.