Police said an explosion occurred in front of the Mahanakhon Building near the Chong Nonsee BTS station and a second in the sidewalk park under the station.
The blast caused the soil from the spot to spill out onto the sidewalk and cause a crack to appear in a glass panel at the station.
The BTS station closed its Gates 2 and 4 following the explosions.
Police said the explosions happened around 7am, at almost the same time at the blasts at the Government Complex in Chaeng Wattana.