Robshaw was presented with the prestigious Pat Marshall Memorial Award after an extraordinary year in which he led England into a new era and Harlequins to their first Aviva Premiership title.
The RUWC on Monday night also honoured Cliff Morgan, the former Wales and British and Irish Lions fly-half, by awarding him the club's special award.
Robshaw won the Pat Marshall award after topping the RUWC poll ahead of England coach Stuart Lancaster, Harlequins fly-half Nick Evans and Argentina captain Juan Martin Fernandez Lobbe.
The 26-year-old had made only one previous Test appearance when he was appointed captain for the 2012 RBS 6 Nations and he led from the front as the new-look England team finished second in the championship.
In May, Robshaw lifted the Premiership trophy at Twickenham after Harlequins' thrilling victory over Leicester in the final. Robshaw rounded off a remarkable year on December 1 by becoming only the sixth England captain in history to taste victory over New Zealand.
Morgan was honoured as one of the greatest players ever to have emerged from these shores. He won 29 caps for Wales and four for the Lions before moving into a successful career in broadcasting.
Morgan was unable to attend the awards dinner in London but he sent an emotional message of thanks.
He said: "What a lovely honour you have given me from the Rugby Union Writers' Club. An award of such graciousness is to be loved and treasured. Thank you. I am extremely honoured. Have your usual wonderful dinner and my greetings to you all.
"As the ancient poet wrote: 'Many people walk in and out of your life but only true friends leave footprints in your heart'. That is what our wonderful game of rugby has given me - many true and dear friends."
- Sports & Recreation
- Cliff Morgan