Myanmar was rattled by a series of small blasts across the country in October 2013 which appeared to target tourist spots as the emergent nation experienced an influx of foreign visitors following its switch two years earlier from junta rule and the subsequent lifting of many western sanctions.
Yangon's western district court on Friday convicted Saw Myint Lwin of planting two devices in the commercial hub, one of which was a small bomb that exploded inside the luxury Traders Hotel, the Mirror newspaper reported.
The unnamed American woman was taken to hospital with wounds to her thigh and her hand after the blast ripped through a guest room in the downtown hotel, which has since been rebranded the Sule Shangri-La.
Two other men were acquitted of planting bombs, the Mirror reported.
The 29-year-old was arrested days after the blast with police saying he stayed in the same room where the bomb was placed.
At the time an unnamed source from the Karen National Union (KNU) rebel group told AFP that Saw Myint Lwin was a member and that he may have been dissatisfied with ongoing peace talks.
Explosions were relatively common under the former junta, which usually blamed the blasts on armed exile groups or ethnic rebels.
Tourists are rarely targeted.
Myanmar's quasi-civilian government and a myriad of ethnic armed groups are still in ongoing negotiations to sign an elusive nationwide ceasefire agreement.
Observers say it is unlikely to be finalised before crunch elections later this year.