The present invention provides a modified release dosage form of tacrolimus that releases two or more amount of tacrolimus upon oral administration, the first amount of tacrolimus releases from the immediate release dosage unit substantially immediately within 0-2 hours followed by a time interval ranging from about 1-10 hours during which substantially no amount of tacrolimus is released from the dosage form, after which a second amount of tacrolimus is released wherein said second amount is released from the delayed release dosage unit either immediately e.g. within 0-2 hours or over a period of time ranging from about 2-12 hours from its initial release from the delayed release dosage unit. The dosage form may further comprise additional amount of tacrolimus to provide additional pulse of tacrolimus. The dosage forms of tacrolimus exhibit improved bioavailability and reduced flux or fluctuation over existing composition of tacrolimus. A method of preparing the dosage forms is also described.