Security was tightened along the route from the high-security Bangkok Remand Prison where he was detained to the Court, The Court’s ruling means police can detain him for a further 12 days.
Hazaei has been charged with conspiracy to make and possess explosive devices intended to cause harm to others.
Police investigators said they opposed bail, citing possible flight risk as the case concerned serious offences with severe punishment. In addition, the explosive devices found were especially powerful and destructive, posing a threat to the public. The suspect, if released, might tamper with witnesses or evidence.
Hazaei was arrested at Suvarnabhumi Airport on February 14 as he was about to board a flight to Malaysia.
Arrest warrants have been issued for five suspects, with two suspects still at large, and police are gathering evidence to seek an additional arrest warrant for a sixth suspect.
Thailand on Tuesday sent a request to Malaysia for the extradition of Masoud Sedaghatzadeh, a suspect in the same case. He was arrested by Malaysian authorities in Kuala Lumpur, one day after three explosions in Sukhumvit area.