Aim To use ultraviolet (UV) radiations in an indigenous method for sterilization of respirators for reuse during COVID-19 outbreak. Background COVID-19 outbreak has infected more than 200 countries. In India, till now, more than 100,000 cases have been reported. Healthcare workers are at high risk of developing infections being in the frontline of taking care of COVDI-19 cases. The demands of personal protective equipment (PPE) are increasing, but the same is not matched with supply due to various reasons. In such scenarios, reusing respirators and face shields is an alternative. UV radiations have quick action and are able to preserve the quality of respirators. We have developed a UV box for surface sterilization of respirators with an intention to reuse. Technique A thermocol box was taken from the central drug store and was fitted with two UV tubes of 254 nm wavelength procured from local service center of water purifiers. The position of the two tubes was such that one was near the base while other was fixed at the top. An aluminum mesh frame was placed in the middle of the box to act as a platform. The roof of the box was converted into a lid. The effectiveness of assembly was tested using culture of Escherichia coli and Staphylococcus aureus . In addition, a biological indicator tube containing test strip with spores of Bacillus atrophaeus was also exposed to UV light for a predefined duration, which did not show any color change after incubation for 48 hours. Conclusion Our prototype assembly with supported efficacy from microbiological tests is an option for use of UV light within available resources for disinfection and reuse of scarce supplies of personal protective equipment. Clinical significance UV box can help in meeting the demand supply deficit for respirators, face shields, and goggles that are paramount for the protection of HCW. How to cite this article Kumar P, Chaudhry D, Parmar A, Tyagi D, BG Manjunath, Singh PK. Ultraviolet Box: An Innovative In-house Use of Ultraviolet Irradiation for Conservation of Respirators in COVID-19 Pandemic. Indian J Crit Care Med 2020;24(8):713–715.