Yechury met Tarigami on Thursday amid tight security at his residence in Srinagar where he is under house arrest.
Addressing reporters after returning, Yechury said: "I visited Tarigami and enquired about his health. I will file an affidavit in the court regarding his health condition and also report on what I saw there."
He said during the drive from the airport to Tarigami's house, "I saw that the situation on the ground was completely contrary to what the BJP-led government was saying".
Yechury was allowed to go to Kashmir by the Supreme Court which heard his petition challenging Tarigami's detention ahead of the abrogation of Article 370 by the government on August 5.
He is the first opposition leader allowed to visit Kashmir after the government revoked Article 370 on August 5.
On Thursday, Yechury drove from the Srinagar airport in a security convoy and reached Tarigami's Gupkar Road residence at noon. The media was barred from going close to Tarigami's residence and the stretch of road leading to it was kept out of bounds.
Yechury met Tarigami on his third visit to Kashmir since the abrogation of Article 370. On the previous two times, he had been sent back from the Srinagar airport.
On August 24, Yechury, along with a dozen other opposition party leaders including former Congress President Rahul Gandhi were sent back to Delhi from the airport.
On August 9, he, along with CPI General Secretary D. Raja, were also detained at the Srinagar airport and sent back to Delhi.
( With inputs from IANS )