This study examined the effect of sustainability reporting on the financial performance of listed environmentally-sensitive companies in Nigeria. Specifically, the study examined the effect of sustainability on Return on Assets (ROA) and Return on Equity (ROE). Ex-post factor design was employed as data were extracted from published audited annual financial reports of 23 sampled listed companies on the Nigerian Exchange Group for a period of ten (5) years covering 2016-2020. A disclosure checklist was adapted and modified in collecting data for the independent variable (sustainability reporting). The data collected were processed and subjected to series of tests to ascertain their validity and reliability. Multiple analysis was used. Findings of the study show that sustainability reporting has insignificant positive effect on ROA and insignificant negative effect on ROE of listed environmentally-sensitive companies in Nigeria. Therefore, the study recommends amongst others that managers of listed environmentally –sensitive companies in Nigeria should monitor their efforts in the area of sustainability reporting.