My 1999 Accord (2-door, V6 engine) won't start. Battery is OK. I hear the same noise as usual but the engine just does not start. Any one would help or have a piece of advice? Appreciate!

Perform tests, in Sections 1 and 2, below:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563.html

If the CEL comes on and goes off after 2 seconds, when the ignition switch is turned to ON (Position II), and you can hear the fuel pump run, the Ignition Control Module (ICM) and coil may need replacing:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-4.html#post265896

This is a common problem on Hondas of this generation.