The analysis of the effects of propolis products as food supplements on the viability of baby hamster kidney (BHK-21) and murine macrophage (RAW 264.7) cells by spectrophotometric MTT assay ABSTRACT Propolis is beeswax with rich bioactive compound content. On the market, there are many propolis products as food supplements for the consumers. This study aimed to investigate the effect of food supplement products based on propolis at several concentrations on the viability of baby hamster kidney cells and murine macrophage cell lines (BHK-21 and RAW 264.7). For this purpose, both cell lines were treated with the two-fold serial dilutions (from 20 to 2-10) of each six propolis products (P1, P2, P3, P4, P5 and P6) after reaching monolayer cell in 96-well microplates. The viability and inhibition of cells were spectrophotometrically determined by MTT assay after 24 h. For BHK-21, the CC50s of P1, P2, P3, P4, P5 and P6 were calculated as 0.003, 0.178, 0,082, 0.451, 0.278 and 0.384 %, respectively. For RAW 264.7, the CC50 of P1, P2, P3, P4, P5 and P6 were calculated as 0.260, 0.218, 0.115, 0.257, 0.207 and 0.265%, respectively. The CC50 value was higher for RAW 264.7 cells than for BHK-21 cells. So, the low cytotoxic effect was determined in RAW 264.7 cells. Propolis products containing some additives (aroma, flavoring) had lower the CC50 and the lower viability of BHK-21 cells. So, Additives in the propolis food supplement might be an effective factor on cell viability as much as dilution factor and propolis content.