This marks the latest bust in a campaign by Jordanian authorities to curb large flows of narcotics, particularly Captagon amphetamine pills, from areas in Syria under the control of President Bashar Al Assad, whose government was re-admitted to the Arab League in May.
The police spokesman said security personnel had received information about "large quantities" of drugs hidden "by unknowns" in the jointly operated Jordanian-Syrian Free Trade Zone, near the main Nassib border crossing between the two countries, in the last several days.
"After intelligence efforts, the dealer to whom the drugs belonged was identified and arrested," the spokesman said.
Police did not identify the dealer, only describing him as having been "in partnership with international drug smuggling gangs".
Among the seized drugs were three kilogrammes of crystal methamphetamine and 15,000 Captagon pills, the spokesman said. Both of these drugs can be manufactured in clandestine drug laboratories.
In a separate case, security forces in the north-eastern governorate of Mafraq arrested a "dangerous" drug suspect who is accused of inciting people "to shoot narcotics personnel".
A special forces unit arrested the man after "solidly trapping him and his brother".
"They had automatic weapons and ammunition," the spokesman said.
Mafraq is a main conduit for the smuggling of drugs from Syria to Saudi Arabia, officials said. The area's inhabitants are mainly members of tribes and clans with ties to Iraq and Syria, who have traditionally formed the main support base for the Hashemite monarchy.
Jordan's ties with Damascus, which have traditionally been tense over a range of political issues, deteriorated after the 2011 revolt against Mr Al Assad's 22-year rule. In the ensuing civil war, large regions of southern Syria, near the border with Jordan, fell to rebels supported by Amman and other Arab and western countries.
After a deal between Russia, the US and Israel, the Syrian military recaptured these areas in 2018, and Captagon smuggling spiked. Jordan said that the flows were being overseen by the Syrian army and its Iran-backed militia allies.
Amid rapprochement between the two countries, Jordanian and Syrian security officials met in Amman last month to discuss ways to curb the smuggling. Neither side released any details of the talks or their outcomes.
Jordan is pursuing what officials call a step-for-step approach to solving problems emanating from Syria. It wants to see co-operation from Damascus on Captagon and other issues before it can support Mr Al Assad in strengthening his regional position.