One of the most significant illnesses that has a negative impact on the standard of living of people all over the globe is diabetes mellitus (DM). There is currently no drug on the market that can completely treat diabetes and all of the issues that come with it, much alone keep a person in excellent health. Traditional medicine, which is mostly derived from medicinal plants (MPs), is used to treat a variety of illnesses and conditions, including diabetes and the consequences of the disease. There are several papers that give evidence that many MPs exhibit anti-diabetic activity (ADA), and yet there are still many TMs that have not been researched about their ADA. Therefore, the purpose of this research was to assess the anti-diabetic activity (ADA) of Sida veronicefolia on diabetic mellitus that was caused by Alloxan in WISTAR albino rats. The phytochemical examination performed on the extracts of Sida veronicefolia indicates the existence of a variety of distinct phytochemical components. These components include sterols, terpenoids, alkaloids, flavanoids, and so on. The anti-diabetic effect of the methanolic extract was dosage dependent, similar to that of the standard medication metformin. The extract considerably regulated the amount of glucose in the blood, led to a reduction of body weight, and caused changes in a variety of enzymes involved in lipid metabolism. The findings of the current study provide scientific credence to the traditional use of Sida veronicefolia, and more studies are now being conducted to investigate its wide range of pharmacological applications and to determine which of its constituents contain bioactive compounds.