Ryan Kelly was born in Hazelton, Pennsylvania. He began his ballet training at the age of 13 with Trinette Singleton in Wilkes-Barre, Pennsylvania, and Marcia Dale Weary at the Central Pennsylvania Youth Ballet. Mr. Kelly attended the School of American Ballet (SAB), the official training school of New York City Ballet, for two years before joining the Company during the 1998 Saratoga Springs Season.

Upon joining New York City Ballet, Mr. Kelly danced numerous ballets from the Company's vast repertory, including George Balanchine's Brahms-Schoenberg Quartet, Chaconne, Cortège Hongrois, Donizetti Variations, Firebird, A Midsummer Night's Dream, George Balanchine's The Nutcracker™, Prodigal Son, Slaughter on Tenth Avenue (Cop), La Sonnambula, Square Dance, Stars and Stripes, Stravinsky Violin Concerto, Swan Lake, Tschaikovsky Suite No. 3, Union Jack, La Valse, Vienna Waltzes, and Western Symphony; Peter Martins' Fearful Symmetries, The Sleeping Beauty, and Swan Lake; Jerome Robbins' The Concert, Fanfare, The Four Seasons (Fall), I'm Old Fashioned, In G Major, In Memory Of..., and Opus 19/The Dreamer; and Robert La Fosse's and Robert Garland's Tributary.

Following his time as a dancer at NYCB Mr. Kelly has developed his own choreography. His first ballet, set on the Central Pennsylvania Youth Ballet, was accepted into the Regional Dance America Festival. He has since created works for SAB and other RDA companies, winning an award in 1999 for best new choreography of the South East Festival. In April 2000, New Choreographers on Point presented his newest work in Ballet Builders 2000. Mr. Kelly was also one of the first choreographers to participate in the New York Choreographic Institute in September 2000.

In September 2002 Ryan Kelly and Brennan Gerard produced The Performance Project, a weeklong festival of performance on New York's Lower East Side. The project has since developed into Moving Theater, an artists' collective focused on the collaborative generation of multi-disciplinary performance work. In 2004 Moving Theater was presented at Studio 303 in Montreal and at the Joyce SoHo in New York City.