Antoine Semenyo opened the scoring, poking home a rebound before a Michael Morrison own goal doubled their lead.
A second half John Swift penalty wasn't enough to draw Reading level, which now leaves them looking dangerously over their shoulder as they are just two points clear of the relegation zone
Here is a warmdown of the game, going over the key talking points from Ashton Gate.
Alex Scott is a star in the making
The 18-year-old has been one of the Robins' best players this season and has been attracting the interest of many Premier League clubs.
It is certainly clear to see why, with the midfielder having a great passing ability as shown in the game against the Royals. 74 touches, 50 completed passes, an 80% pass completion rate and one key pass on Wednesday evening highlights his impressive performance.
Reading need a change - and fast
The loss against Bristol City is now Reading's sixth consecutive loss in the Championship, and it would appear to outsiders that Veljko Paunovic has little to no time left. However, it doesn't look likely that he will be sacked before the end of the season due to Reading's financial situation.
Despite an energetic last 15 minutes, Reading never looked like getting anything from the game for the first 75 minutes and it was too little too late for the Royals. Reading need to start playing like they did for the last 15 for the full 90 minutes, otherwise, they look in serious danger of going down to League One.
Both sides lack cutting edge
The form had been bad of late for both of these clubs and for large parts of the game, you could clearly see why.
Both sides were not great going forward, Reading being the worst of the two, misplacing key passes, lacking any attractive runs and poor finishing in the final third. If these two are going to get a consistent run of form, they need to be putting the ball in the back of the net on a regular basis.