Abstract: Five observation stations are set up at the mouth, west side, center, east side and north top of the bay. Based on the tidal level and current data observed by many times from winter 2018 to autumn 2020, the harmonic analysis and calculation of tidal current are carried out by means of least square method. The variations of the tidal current characteristics in the Jiaozhou Bay are analyzed by using the calculation models of vertical mean flow velocity and direction, maximum possible flow velocity and water particle maximum possible migration displacement. The results show that the tidal current type coefficient at each station is less than 0.5 and the absolute value of ellipticity of tidal component M_2 is less than 0.1, being close to 0, indicating that the tidal current in the Jiaozhou Bay belongs to a normal semi-diurnal tidal current and the tidal current movement is dominated by a type of reciprocating motion. The residual current, the maximum possible flow velocity and the water particle maximum possible migration distance at the stations in the bay mouth area all are the maximum. In different seasons the velocity and direction of the residual flow have no obvious regularity. Except for the stations at the west side of the bay, at all other stations the flow direction of the residual current has overall a fixed orientation in different seasons: that is, east by north at the bay mouth, west by north at the central station, south by east at the eastern station and east by north at the northern bay top. The flow directions of the residual current are perpendicular to the adjacent coast at the bay mouth close to the shore, the eastern station and the northern bay top. In the vertical direction, the maximum possible flow velocity and the water particle maximum possible migration distance tend overall to decrease from the surface to the bottom at all stations, but the flow direction keeps basically the same.