Edmund backed up two wins in qualifying with a 6-3 6-2 victory over world number 73 Garcia-Lopez in Beijing.
The 21-year-old from Yorkshire, ranked 54th, goes on to face another Spaniard, Roberto Bautista Agut, who beat John Millman 6-4 3-6 6-3.
Fellow Britons Andy Murray and Johanna Konta are in action on Tuesday.
Second seed Murray will play Italian Andreas Seppi in his opening match, while Konta takes on Hungary's Timea Babos as the British number one looks to maintain her hopes of a place at the season-ending WTA Finals.
American Madison keys, currently three places ahead of Konta in the eighth and final qualifying position, beat Kristina Mladenovic of France 7-5 6-4 on Monday.
There was an upset as China's unseeded Shuai Peng beat American sixth seed Venus Williams 7-5 6-1.
Britain's Kyle Edmund is through to the second round of the China Open following a straight-sets win over Spain's Guillermo Garcia-Lopez.