We compared the effects of an ethylene absorbent and the ethylene inhibitor 1-methylcyclopropene (1-MCP) on tomato (Solanum lycopersicum Mill. cv. Dotaerang) during storage. Tomato fruits at the ‘breaker’ stage were harvested and treated with an ethylene absorbent, 1 μL·L-1 1-MCP or 2 μL·L-1 1-MCP and stored at 20°C for 15 days. We then measured weight loss, peel color, firmness, soluble solids content (SSC), titratable acidity, pH, ethylene production and total phenolic and flavonoid contents in the fruits. Color development occurred more rapidly in the control than in fruits treated with the ethylene absorbent or 1-MCP (1 μL·L-1 and 2 μL·L-1 ) on day 6 and 9. The Hunter a value (redness) of 1-MCP (2 μL·L-1 )-treated fruit on day 6 was 2.24 ± 3.8, while that of the control was 13.39 ± 2.23, indicating that color development was delayed by 1-MCP treatment (2 μL·L-1 was more effective than 1 μL·L-1 ). Ethylene absorbent treatment was not more effective at maintaining fruit firmness than 1-MCP (2 μL·L-1 ) treatment. There was no statistically significant difference in fruit firmness between the ethylene absorbent treatment group and the control. Total phenolic and total flavonoid contents increased in all treatment groups during storage. These contents did not significantly differ among groups on day 15. These results suggest that 1-MCP treatment is highly effective in delaying tomato ripening during storage and that 2 μL·L-1 1-MCP treatment is more effective than 1 μL·L-1 treatment. However, the ethylene inhibitor did not influence the levels of antioxidant compounds compared with the control.