Background: Tamoxifen citrate is a very prevalent drug marketed under several trade names like Apo-Tamox, Nolvadex, Tamec, Tamizam and Tamoplex. This molecule is approved by the FDA for breast cancer treatment. Some studies have shown that tamoxifen has anti-tuberculosis and anti-parasitic activities. Like any drug tamoxifen possesses side effects, more or less dangerous. Aims: Basically, this work is a comparative study which aims to: Primarily compare the antimicrobial and antitumor activities of tamoxifen and a newly synthesized tamoxifen analogue. Secondly, determine the molecule with lesser side effects. Methods: Three groups of mice were injected with tamoxifen citrate and compound 2(1,1-bis[4-(3- dimethylaminopropoxy)phenyl]-2-phenyl-but-1-ene dihydrochloride) at doses corresponding to C1 (1/10), C2 (1/50), C3 (1/100) to compound 2 lethal dose (LD50 = 75 mg/kg) administered for adult mice. A group of not injected mice has served as a study control. Results: Experimental results suggest that compound 2 have better antitumor and antimicrobial activity than tamoxifen citrate besides its lower toxicity effects. Conclusion: The results emerged from the present study confirmed the antitumor and antimicrobial effect of tamoxifen citrate and its hematological side effects. Compound 2 seems to be more effective than tamoxifen citrate for antitumor and antimicrobial treatment while having less hematological side effects and less disruption of the blood biochemical parameters. These findings encourage us to push further studies for compound 2 and test it for other therapeutic usage for which tamoxifen was effective.