The resurgence of popularity of the transconjunctival approach to lower eyelid fat removal as a component of cosmetic blepharoplasty has been highlighted by a number of publications in recent years. There has been, however, minimal discussion in the literature of the complications of this procedure. Although the mechanism of muscle injury is similar in transcutaneous and transconjunctival surgery, there is a much more direct route to the inferior extraocular musculature via the latter approach. Herein, we present a series of six patients with diplopia status post- transconjunctival lower eyelid blepharoplasty referred to the Manhattan Eye, Ear, and Throat Hospital for evaluation. Transconjunctival lower lid blepharoplasty was performed as a primary procedure in four patients and as a secondary procedure following transcutaneous blepharoplasty in two patients. Patients were evaluated with ocular examination and orthoptic measurements. Magnetic resonance imaging was obtained in two cases. The inferior rectus and inferior oblique muscles were found to be equally injured in these cases (4 of 6), and the lateral rectus was encountered in one case. Two patients required strabismus surgery to Correct their diplopia, whereas four patients improved with observation alone. The possible etiologies of postoperative diplopia following transconjunctival lower lid blepharoplasty are manifold. Mechanisms of extraocular muscle injury may include intramuscular hemorrhage and edema, cicatricial changes within the muscle, and accidental incorporation of extraocular muscle in closure of orbital septum. Avoidance of these complications is probably best achieved through intimate understanding on the part of the surgeon of eyelid anatomy from the transconjunctival perspective.