Three other people were wounded at the "Las Torres" bar and were in critical condition, said Arturo Sandoval, spokesman for Chihuahua state prosecutors.
Sandoval said investigators were still trying to determine who was behind the attack.
Ciudad Juarez is the center of a fierce turf war between the Sinaloa and Juarez drug cartels, and has become one of the world's most dangerous cities. More than 3,000 people were killed last year in the city of 1.3 million residents across from El Paso, Texas.
Meanwhile, a shootout between troops and armed men killed nine people in a central Mexican state that his seen a rise in drug violence, the government said Thursday.
The gun battle erupted after soldiers came under fire while investigating a tip about the presence of armed men in Tabasco, a town in the southern part of Zacatecas state, the Defense Department said in a statement.
One soldier and eight gunmen were killed in the fighting Wednesday night, the statement said. Two other soldiers were wounded and authorities seized six assault rifles, three radios and two bulletproof jackets.
The statement gave no details about who the gunmen were but Zacatecas lies between territory controlled by the Sinaloa cartel and area disputed by the Gulf and Zetas gangs, and has recently seen a surge in violence.
In Baja California, 10 soldiers were detained for alleged ties to drug traffickers and turned over to federal prosecutors, the Defense Department said Thursday.
The brief statement said the soldiers were assigned to the 67th Battalion in the Pacific coast city of San Quintin. It said the three junior officers and seven enlisted soldiers were detained Tuesday and flown to Mexico City on Wednesday.
Drug traffickers have been recruiting members of the armed forces for years.
In one of the most shocking cases, Gen. Jesus Gutierrez Rebollo was arrested in 1997 when he was Mexico's drug czar and charged with protecting then cocaine kingpin Amado Carrillo Fuentes, the late leader of the Juarez cartel. Also, the Zetas drug gang was started in the late 1990s by a small group of elite soldiers based in Tamaulipas who deserted to work for the Gulf drug cartel.
Mexican President Felipe Calderon has deployed more than 40,000 troops throughout Mexico since he launched a crackdown against drug traffickers shortly after taking office in December 2006.
Drug gang violence in Mexico has seen nearly 35,000 people killed since then.
In the northern border state of Chihuahua, assailants killed a man who became a local hero after killing three gunmen who had gone to his home to demand extortion money, officials said Thursday.
Alvaro Sandoval Diaz, 50, and his 35-year-old wife, Griselda Pedroza Rocha, were killed Tuesday night in Puerto Palomas, across from Columbus, New Mexico, Sandoval, the Chihuahua state prosecutors spokesman, said earlier Thursday.
Last month, Sandoval Diaz opened fire on four armed men who arrived to extort money from him, killing three. The assailants were members of La Linea, enforcers for the Juarez Cartel, prosecutors said.
Relatives of the couple told the Ciudad Juarez newspaper El Diario on Thursday that the couple's 6-year-old daughter witnessed her parents' killings and that the whole family now planned to leave the town.
"The girl just curled up as she watched how they killed her father and then her mother," the girl's grandmother, who didn't want to be identified, told the newspaper.
Associated Press writer Olga R. Rodriguez in Mexico City contributed to this report.