A B S T R A C T Background: Giardiasis is a common intestinal infection, recently included by the World Health Organization in the ‘Neglected Diseases Initiative’. Despite the efficacy of nitroimidazoles; the main antigiardial chemotherapeutics, adverse effects and resistance enforced developing non-chemical alternatives. The present study aimed to assess the therapeutic efficacy of ethanol extract of olibanum (OL), propolis (PR), and their combination versus metronidazole (MTZ) against Giardia lamblia (G. lamblia) infection. Methods: Sixty Swiss male albino mice were randomly divided into 6 groups; 10 mice each, Group I: normal control (non-treated; non-infected). Group II: infected with G. lamblia cysts, non-treated. On the 6th day post infection (dPI), the remaining 4 infected groups were treated orally with: Group III: (OL). Group IV: (PR). Group V: combination of (OL+PR). Group VI: (MTZ). These mice were subjected to direct parasitological diagnosis of Giardia trophozoite in intestinal exudate, immunochromatographic test for antigen detection and histopathological studies. Results: After 7 days therapy, complete clearance of Giardia trophozoites were in the combination of (OL+PR) and MTZ groups therapy. Lower percentages of reduction (91%) & (83%) were recorded in PR and OL-treated groups, respectively. Histopathological examination showed marked healing of intestinal mucosa using non-chemical combination and different degrees of dysplasia using MTZ, while partial healing was observed using olibanum and propolis separately. Conclusion: Olibanum, PR and their combination were proved to enhance the clearance of Giardia trophozoites; with progressive improvement of the histopathological changes of jejunal mucosa, making good non-chemical alternative antigiardial therapeutics sidestepping the obstacles of MTZ like dysplasia and teratogenicity.