Rouhani arrived in Vienna on Tuesday on the second leg of his tour of Europe, which had already taken him to Switzerland.
While in Austria, he sat down with Iranian expatriates in the country and was welcomed by his Austrian counterpart on Wednesday morning.
After separate meetings with the president and chancellor of Austria, the two countries signed four cooperation documents.
Rouhani also met with Archbishop of Vienna and had a meeting with Director General of IAEA Yukiya Amano in Vienna.
The Iranian president has enhanced political contacts with foreign leaders on ways to save the JCPOA after the US exit.
On May 8, the US president pulled his country out of the JCPOA, which was achieved in Vienna in 2015 after years of negotiations among Iran and the Group 5+1 (Russia, China, the US, Britain, France and Germany).
Following the US exit, Iran and the remaining parties launched talks to save the accord.
Meanwhile, Leader of the Islamic Revolution Ayatollah Seyed Ali Khamenei has underlined that any decision to keep the JCPOA running without the US should be conditional on “practical guarantees” from the Europeans.