The transport minister has said more can and will be done after levels of passenger satisfaction with ScotRail dropped.
The study from Transport Focus found 85% of passengers were satisfied with their journey in autumn 2017, down from 90% in the spring survey.
However, passenger satisfaction levels were above the UK average of 81%, and up from ScotRail's 83% rating in the autumn 2016 study.
The survey found satisfaction levels in autumn 2017 had dropped three points for both punctuality (to 82%) and ticket prices (to 59%) since spring last year.
Transport minister Humza Yousaf said: "The improvement on customer satisfaction levels in comparison to the same period last year is to be welcomed, as is the fact ScotRail remains 4% above the UK average.
"Given that 54% of performance issues are infrastructure-related there is a clear need for the greater devolution and better governance arrangements for Network Rail in Scotland which we have called for so many times.
"We can and will do more to ensure we improve on performance and the customer experience as we continue to help build the best railway Scotland has ever had.
"Through continuous monitoring, Transport Scotland routinely challenge ScotRail and the ongoing independent review by Nick Donavan will look to propose steps to improve performance".
Satisfaction with the level of crowding fell eight points to 71% while there were also concerns over the reliability of internet connections on trains and toilet facilities and the availability of wifi at stations.
The National Rail Passenger Survey of more than 27,000 passengers questioned 1419 ScotRail passengers between September and November 2017.
ScotRail Alliance managing director Alex Hynes said: "This survey shows customer satisfaction has improved compared to this time last year, and is a clear sign of the progress ScotRail is making.
"We aren't complacent, and we're working hard to build the best railway that Scotland has ever had. The investment we are making in new and refurbished trains will deliver faster journeys, more seats, and better services for our customers across Scotland."
The highest ratings for overall satisfaction were achieved by Grand Central (96%), Hull Trains (95%) and Virgin Trains East Coast (92%).
Anthony Smith, chief executive of the independent watchdog, said: "For passengers, it's all about performance. It's essential that the ScotRail and Network Rail continue their focus on ensuring that most trains arrive on time, with few cancellations and with carriages of the right length."
"Transport Focus welcomes the independent review of train services that ScotRail announced earlier this month to further improve performance."