Freddie Mercury wrote it on the piano and guitar first, and Brian May rearranged the song for acoustic 12-string guitar for live performances, also lowering the key by a semitone. May contributed occasional guitar phrases to the original recording and played the swooping harp glissandos by pasting together multiple takes of single chords. The song is an example of Mercury's familiarity with rubato phrasing, showcasing his classical piano influences, notably by Chopin and Beethoven.
With its similar lyrical theme, the Roger Taylor penned single "These Are the Days of Our Lives" would later hearken back to "Love of My Life", twice using the line "I still love you". At the end of "These Are the Days of Our Lives", Mercury simply speaks those words, as he would often do in live versions of "Love of My Life".