Flavin mononucleotide (1,4-butanediamine) Pt(II) complex (7FMN) was synthesized and screened anticancer activity [J. Pharm. Soc. Korea 43(6),762-770 (1999)]. 7FMN have good water solubility and moderate anticancer activiy In this paper cell-cycle specificity and nephrotoxicity were studied. Interaction of DNA with cisplatin and synthesized 7FMN was analyzed by flow cytometry and showed G2 arrest in L1210 cell line. It means that cell-cycle on L1210 was inhibit in S phase by cisplatin and 7FMN. In order to biochemically analyze nephrotoxicity of cisplatin and 7FMN, after injecting each agent intraperitoneally, blood was exsanguinated after 6 hours, 1 day, 3 days and 7 days, respectively. Then, serum was separated from the blood. The serum level of BUN, creatinine and uric acid in cisplatin and 7FMN administated mice (25~35 g, ICR strain, a dose each 8,12 and 16 times of the $IC_{50}$/ value, cisplatin; 7 times) were determined by autochemistry analyzer. In cisplatinadministered mice group, BUN level was elevated than normal control group at 3rd day and repaired at 7th day. In 7FMN administrated group was not elevated. Creatinine and uric acid level were no difference with the normal control group. Therefore synthesized 7FMN is less toxic than cisplatin in nephrotoxiciaty.