Purpose  To evaluate the impact of implant length on failure rates between short (<10 mm) and long (≥10 mm) dental implants.   Materials and methods A search was undertaken in three electronic databases, complemented by manual search of some journals. Implant failure was the outcome evaluated, with the estimate of relative effect expressed in risk ratio (RR). Heterogeneity among studies was evaluated by I2statistic. Inverse variance method was used for random- or fixed-effects models. Quality assessment of the studies was performed, and a funnel plot was drawn. A meta-regression was performed in order to verify how the RR was associated with the follow-up time.   Results The reviews included 353 publications. Altogether, there were 25,490 short implants and 159,435 long implants. Pairwise meta-analysis showed that short implants had a higher risk of failure than long implants (RR 2.437, p<0.001). The meta-regression observed that the follow-up time did not have any effect of the RR of failure between short and long implants. A sensitivity analysis plotting together only the studies with follow-up up until 7 years, resulted in an estimated increase of 0.6 in RR for every additional month of follow-up.   Conclusion Short implants showed (< 10 mm) a 2.5 times higher risk of failure than long implants (≥ 10 mm). Implant failure is multifactorial and the implant length is only one of the many factors contributing to the loss of implant. A good treatment plan and the patient’s general health should be taken into account when planning for an implant treatment.       Keywords: dental implant, failure, implant length, systematic review, meta-analysis