The 162-game MLB season had been scheduled to start on March 26 with all 30 teams taking the field.
"This action is being taken in the interests of the safety and well-being of our players, clubs and our millions of loyal fans," the league said in a statement.
"MLB will continue to evaluate ongoing events leading up to the start of the season."
The league added that it will announce the effects on the schedule at an appropriate time and will remain flexible as events warrant, with the hope of resuming normal operations as soon as possible.
"Players are of course disappointed they won't be able to compete on the field," said Tony Clark, executive director of the Major League Baseball Players Association.
"At the same time, they recognize the importance of public health and safety."
The delay marks the first time the MLB season has not begun on schedule due to a non-labor-related issue.
The start of the 1972 and 1995 seasons was delayed due to strikes and the beginning of the 1990 season was postponed due to a lockout, although in all three cases the seasons got underway before the end of April.
The National Basketball Association on Wednesday suspended its season until further notice after a player on the Utah Jazz tested positive for the virus.
Earlier on Thursday, the National Hockey League and Major League Soccer suspended their seasons due to the global outbreak.
The NCAA also called off its annual 'March Madness' college basketball championships on Thursday.