Although involved in opera conducting in a period when in Italy opera was dominating over instrumental music, Rolla continued to compose, maintaining the Italian instrumental tradition high. He wrote about 500 works, from didactic compositions to sonatas, quartets, symphonies, concertos for violin, and at least 13 concertos and other works for viola and orchestra. Significant was his contribution to the dissemination of Beethoven's works in Italy and his familiarity with Beethoven and other Viennese composers is shown in his compositions.