The West Zone of the Ranji Trophy, 1965-66 saw the participation from a number of 5 teams, all coming from the Western region of India. The teams that took part in the tournament under the West Zone included the likes of Maharashtra, Bombay, Baroda, Gujarat and Saurashtra. Though all the teams tried their best to get a chance into the knock out level of the tournament, only the teams like Bombay and Maharashtra became successful to do so from the West Zone. They went on to compete with the top teams of the other zones in the knock out level of the tournament.

The West Zone league matches in the Ranji Trophy, 1965-66 started withy the match between the teams of Saurashtra and Baroda and the match was played at Rajkot from 06-08 November, 1965. The drawn match saw the Baroda team earning 5 points and Saurashtra earning 3 points from it. The teams of Bombay and Gujarat then clashed with each other in the next match of the zone and they played the match at Surat from 06-08 November, 1965. The Bombay team got a very good start in yet another edition of the Ranji Trophy, as the team won the match by a margin of 8 wickets and earned 8 valuable points from the match. The third match of the West Zone was played between the teams of Gujarat and Saurashtra at Junagadh from 13-15 November, 1965. The match saw the Gujarat team winning by a good margin of an innings and 14 runs and also earning 8 points from it.

The teams of Bombay and Maharashtra met with each other in the fourth of the West Zone league matches in the Ranji Trophy, 1965-66 at Bombay from 13-15 November, 1965. The match was drawn during the stipulated duration and the match officials awarded the Bombay and Maharashtra teams 5 and 3 points, respectively for the match. There was a clash between the teams of Maharashtra and Baroda in the next match of the zone and the match was held at Karad from 20-22 November, 1965. This match also remained drawn during the specified duration and the Maharashtra and Baroda teams earned 5 and 3 points, respectively from the match. The Bombay team then played against the Saurashtra team in the sixth match of the zone and the match that was held at Bombay from 21-23 November, 1965, saw the Bombay team winning by an innings and 140 runs. The Bombay team also earned 9 points from the match.

In the seventh of the West Zone league matches in the Ranji Trophy, 1965-66, the teams of Baroda and Gujarat clashed with each other at Baroda from 27-29 November, 1965. The drawn match saw the Baroda team earning 5 points and Gujarat earning 3 points from it. The next match of the zone saw a battle between the teams of Maharashtra and Saurashtra at Nasik from 27-29 November, 1965. The Maharashtra team played wonderfully and won it comprehensively by a margin of 169 runs to earn 8 valuable points from the match. The teams of Bombay and Baroda then met with each other at Baroda from 04-06 December, 1965 and the match was drawn during the stipulated duration. The Bombay team earned 6 points and Baroda earned 3 points from the match. The last of the West Zone league matches in the Ranji Trophy, 1965-66 involved the teams like Gujarat and Maharashtra and the match took place at Anand from 11-13 December, 1965. Playing well in the match, the Maharashtra team clinched a victory of 7 wickets for earning 8 valuable points.