A bicycle operating device comprises an operating unit, a mounting member, and a positioning structure. The operating unit includes a first portion. The mounting member includes a second portion configured to be connected with the first portion of the operating unit. The positioning structure is configured to adjustably position the first portion with respect to the second portion in a first direction and a second direction. The positioning structure comprises an abutment member and a fixing member. The abutment member is arranged opposite to the first portion with respect to the second portion. The fixing member is configured to fix the second portion with respect to the first portion by sandwiching the second portion between the first portion and the abutment member.