CP Rizwan scored a second half-century in as many days, but UAE fell to another damaging defeat at the start of their troubled tour of Texas.
The national team followed up their four-wicket loss to Scotland in the opening match of their Cricket World Cup League 2 series with a matching result against the United States.
For the second day running the batters struggled to come to terms with a wicket at the Moosa Cricket Stadium, which bears a striking resemblance to that which they are so used to in Sharjah.
Rizwan followed up the 55 he made against Scotland with 67 this time against the home team, but he had little support.
Ali Khan, the fast bowler who has represented Kolkata Knight Riders in the Indian Premier League, took two wickets, as did Cameron Stevenson, as UAE were limited to 203 for seven from their 50 overs.
The hosts were troubled little in reply, despite the best efforts of UAE captain Ahmed Raza, who took three wickets and two fine catches.
Sushant Modani top scored with 70 in the chase, and shared a stand worth 102 with captain Monank Patel for the second wicket.
United States reached their target with 31 balls to spare.
The result means UAE, whose plans have been derailed by a shoulder injury for allrounder Rohan Mustafa, have now lost all three matches against the United States in this competition.
A new-look national team were beaten twice by the same opposition in matches in Dubai and Sharjah back in 2019.
The latest result meant USA were able to close the gap to the UAE in the points table. They are in fourth, four points behind the national team having played a game less.
The top three sides in the tournament will advance to the World Cup Qualifier, where they will play for the final two berths at the main competition, in India next year.
UAE will seek to get their campaign back on track when they face Scotland on Friday.