Healy announced his decision to quit on Tuesday after failing to find a club following his release by Bury at the end of last season.
The 34-year-old enjoyed an outstanding career, scoring an incredible 36 goals in 95 appearances for his country, including the winner against England at Windsor Park in 2005.
And Moyes played a significant part in Healy's footballing life, snapping him up from Manchester United in 2001 when he was Preston boss - a move that almost paid rich dividends within a matter of months as the Lancashire outfit were beaten in the Championship play-off final by Bolton.
"He was fantastic for us," Moyes said.
"I remember phoning Sir Alex about him and paying about £1.5million, which was quite a lot of money at that time.
"He came in the January when we had about 20 games to go. He scored 10 goals in those 20 games and got us to the final when we lost to Bolton.
"He was a brilliant goalscorer. He could score from tight angles and possessed a real strength in his shooting for a small guy.
"He had come from good stock at Manchester United and we really liked him. He was a great boy to work with."
Having a Northern Irish background himself, Moyes took a lot of pride in helping to forge the career of a player from the country.
And, while it was not long before he moved on to Everton for 11 years, and now United, Moyes kept an eye on Healy's career and feels he deserved to be acknowledged as one of Northern Ireland's best.
"I have a lot of fondness for boys from Northern Ireland because my mother was from there," Moyes said.
"He went on to be one of that country's greats.
"In a period when Northern Irish football was just dropping, he was the one who kept it going because he was able to get them a goal in big games.
"His goals per game ratio was remarkable."