Background: Pediatric femoral shaft fractures are common orthopaedic injuries. Conservative management with early spica casting or traction followed by spica casting is considered the standard treatment. Recently, light have been thrown on internal fixation especially elastic stable intra-medullary nailing (ESIN). Studies were done to assess the efficacy and safety of ESIN, but few compared its results with conservative management. Patients and Methods: Between May 2013 and January 2014, a randomized controlled study was conducted on 33 patients with unilateral pediatric femoral shaft fractures. The subjects were divided into 2 groups; a group managed with TEN, the other was treated conservatively. In the TEN group there was 17 patients, with a mean age of 7.5 years (4-15). In the conservative group we treated 16 patients. Their mean age was 7.7 years (4-12). In the ESIN group, 2 TEN were introduced in a retrograde fashion. Nail size was chosen that both nails occupied 80% of the narrowest canal diameter (NCD). Only one patient required spica immobilization post-operatively. For patients treated conservatively, skin traction was applied for 2-3 weeks. Weekly follow-up x-rays were done waiting for soft callus, then the patient was put in one and half hip spica for mean of 4.5 weeks. Results: Out of 33 patients, 30 were followed-up and assessed for a mean of 6 months; 15 in each group. Two patients were lost to follow-up from the operative group and 1 was excluded from the conservative group due to underlying metabolic bone disease. At the last follow-up, patients in the operative group were 9 (60%) excellent, 3(20%) satisfactory, 3(20%) poor according to Flynn’s scoring criteria. In the conservative group, 3(20%) were excellent, 4(26.7%) were satisfactory, 8(53.3%) were poor. We found statistically significant difference between both groups regarding angular deformities (p-value 0.003 for saggital angulations and 0.033 for coronal angulations), knee range of motion at 3 and 6 months follow-up (p-values 0.011 and 0.003 respectively), hospital stay (p-value 0.000) and total Flynn’s score (p-value 0.03). Spica casting was significantly cheaper than ESIN (p-value 0.000). There was no statistically significant difference between both groups; regarding age (p-value 0.45) and time to union (p-value 0.29). Regarding LLD, there was a significant difference at 3 months follow-up (p-value 0.001) which was abolished at 6 months (p-value 0.07). Conclusion: Conservative management is cheaper than operative management with ESIN. ESIN is a safe and efficient method of treatment that supersedes conservative management in shorter hospital stay, earlier knee range of motion, less angular deformities.