The LAPD and the city council hope the reward will convince those with information of the shooting to come forward.
Councilman Eric Garcetti announced the reward at City Hall on Tuesday. The violent shooting occurred outside Principe de Paz Church located at Beverly Boulevard and Reno Street in the Rampart area of Los Angeles Sunday night.
Investigators say Andres Ordonez, a 25-year-old deacon at Principe de Paz Church, confronted a woman spray painting graffiti on an exterior church wall when a suspected gang member got out of a car and opened fire.
Ordonez was fatally shot and another man was wounded.
The woman and the shooter are both believed to be gang members.
Principe de Paz Church's congregation held a prayer service Monday night to honor Ordonez, who leaves behind a pregnant wife and a year-old son.
There have been no arrests. There were no descriptions of the suspects nor the getaway vehicle used.
Police hope new information will come in light of the reward.
Anyone with information is urged to call the Los Angeles Police Department at (877) LAPD-24-7.