In order to meet the needs of large-capacity data transmission and equipment miniaturization of communication equipment, a multi-mode reconfigurable terahertz microstrip antenna including rectangular chip, media substrate and slotted floor is proposed in this paper. Based on the electrically controllable characteristics of graphene materials in the terahertz band, 3 groups of graphene are distributed as regulator switches in the slotting, and the switch is switched off by controlling the bias voltage of graphene. The antenna has 6 frequency reconfigurable modes, the resonant frequency is distributed in the range of 2.652-4.565 THz, the -10 dB bandwidth is greater than 10%, the maximum radiation gain is 2 dBi, and the reflection coefficient is lower than -15 dB, showing good radiation characteristics. The use of a single group of graphene as a fine-tuning control unit can realize the tunable function of the antenna in the small frequency range, which has great application potential in the design of graphene terahertz reconfigurable antennas and antenna arrays.