According to Catholicism, did St. Paul believe that end of the world was imminent? We read at 1 Cor 7: 29-31 (NRSVCE) :

I mean, brothers and sisters, the appointed time has grown short; from now on, let even those who have wives be as though they had none, and those who mourn as though they were not mourning, and those who rejoice as though they were not rejoicing, and those who buy as though they had no possessions,   and those who deal with the world as though they had no dealings with it. For the present form of this world is passing away.

The said words of St. Paul apparently point to his view that the end of the world was imminent. My question is : According to Catholic Church, did St. Paul believe that the end of the world was imminent?
The Catholic Church has a nuanced approach to Biblical inerrancy. A dogmatic constitution of the Second Vatican Council states inerrancy applies only to

that truth which God wanted put into sacred writings for the sake of salvation [and that]
the interpreter of Sacred Scripture, in order to see clearly what God wanted to communicate to us, should carefully investigate what meaning the sacred writers really intended, and what God wanted to manifest by means of their words. -  Dei Verbum

So it would seem possible that Paul could be wrong in a technical sense that &quot;time has grown short&quot;, as far as the Catholic Church is concerned, while still conveying what God 'wanted to communicate to us' in 1 Corinthians.
If we turn to the Catholic Encyclopedia it states:

A common characteristic of all these passages [in Thessalonians] is the apparent nearness of the parousia. Paul does not assert that the coming of the Saviour is at hand. In each of the five epistles, wherein he expresses the desire and the hope to witness in person the return of Christ, he at the same time considers the probability of the contrary hypothesis, proving that he had neither revelation nor certainty on the point. He knows only that the day of the lord will come unexpectedly, like a thief (1 Thessalonians 5:2-3), and he counsels the neophytes to make themselves ready without neglecting the duties of their state of life.

However, you are asking about St. Paul's personal belief on this matter, not exactly what he may have written in his canonical epistles. Did St. Paul write inerrantly in 1 Corinthians? I believe the Church would say yes as far as what God thought important to communicate to us with that text. But was St. Paul's personal belief about 'end times' correct? I have not been able to find anything stating one way or the other on this as far as official Catholic teaching, so my answer is no, the Catholic Church does not officially hold that St. Paul believed that the end of the world was imminent.