John Dill Robertson (March 8, 1871 – August 20, 1931) was an American medical professional and politician. He served as Chicago's city health commissioner, president of the Chicago Board of Education, and president of the Chicago West Parks Board. In 1927, Robertson ran a third-party campaign for Chicago mayor. As a politician, Thompson was affiliated with the Republican Party. He was an ally of Republican boss Frederick Lundin, and prior to his 1927 mayoral campaign against him, had also long been an ally of William Hale Thompson.

During Robertson's tenure as health commissioner, the city was impacted by the pandemic of the 1918 Spanish flu. After the pandemic receded in the city, Robertson successfully worked to promote legislation to make it easier to become a registered nurse in Illinois, after noticing the necessity of more registered nurses during the outbreak. Also during his tenure as health commissioner, a 1921 decision by the Supreme Court of Illinois greatly weakened the authority of the office.

Robertson was born on March 8, 1871, in Mechanicsburg, Pennsylvania. Robertson, as a young man, worked as a telegraph operator.

He moved to Chicago to attend Bennett Medical College, graduating in 1896.

In 1898, after serving as an intern at Cook County Hospital, he was appointed attending surgeon, a position he held there through 1913. He was also surgeon-in chief at Jefferson Park Polyclinic Hospital from 1904 through 1915.

Robertson organized the American College of Medicine and Surgery in 1900, and was its president until it merged with Loyola University Chicago's own medical school.

Politically, for many years, he would be a close associate of Republican political boss Frederick Lundin. He would also be an ally of Mayor William Hale Thompson.

For seven years, under Mayor William Hale Thompson, Robertson served as City Health Commissioner. He was appointed in 1915, succeeding George B. Young, and served through 1922.