An optical fiber sub-assembly includes: a handle, a rear retainer, an optical cable, a field mountable connector (FMC) assembly, a spindle, and a protection hood fixedly connected to the spindle. An end of the optical cable is connected to the FMC assembly, the optical cable protrudes from a first end of the FMC assembly. The FMC assembly includes a ferrule provided at a second end of the FMC assembly. The spindle is sleeved outside the first end of the FMC assembly, and the protection hood is sleeved outside the second end of the FMC assembly. An end of the spindle that is away from the protection hood is connected to the rear retainer and is used to fasten the optical cable. The handle is sleeved outside the protection hood and the spindle.