Johannes "Jan" Antonius Constantius Marie Grijseels (October 6, 1890 - May 10, 1961) was a Dutch track and field athlete, who competed in the 1912 Summer Olympics. He was a seventeenfold Dutch champion in all track events running up from 100 to 800 metres.[1]
Grijseels was born in Abcoude-Proosdij and died in Noordwijkerhout.
In 1912 he was eliminated in the semi-finals of the 200 metres competition. In the 100 metres event he was eliminated in the first round.