James Hamilton Calder (born 20 August 1957) is a former Scotland international rugby union player. In 1983 he toured New Zealand with the British Lions and at the time played club rugby for Stewart's Melville FP. His international debut came in 1981 aged 21 against France. Scotland were on the receiving end of a 16-9 loss. He scored the winning try in Scotland's 21-12 victory over France at Murrayfield in 1984 which gave Scotland its first Grand Slam since 1925.
His twin brother, Finlay Calder, also played for Scotland and captained the 1989 British Lions tour to Australia. The brothers never played in the same Scotland side; Jim Calder won the last of his caps against Wales in March 1985 and Finlay made his debut against France in January 1986. Jim won a total of 27 caps, with his career record ending as: Won 12, Lost 13, Drew 2.
His two sons, Duncan and Lewis, have also represented Scotland at U21 level. Duncan, his elder son, retired from the game due to knee problems.