Paired with three-time Japanese Olympian Yuya Oikawa, Greig lasted barely 30m before falling heavily to the Adler Arena ice.
Oikawa went on to complete the race and lie 17th overall with 35.24sec, while Greig picked himself up to skate across the line in 80.55.
The 500m is skated twice, with the final result based on the total time of two races.
The result is particularly disappointing after Greig won silver at the world sprint championships in Japan last month over 500m.
Greig, 22, is also scheduled to contest the 1000m on Wednesday.