Objectives: There is a possibility for exposed lactating mammalians to transfer some contaminants to their milk. This study aimed to determine the levels and changes of Zearalenone (ZEN), Deoxynivalenol (DON) mycotoxins for the first five months in human milk. Methods: Voluntary lactating mothers having infants with gestational length ≥ 37 weeks were enrolled between August 2017 and June 2018 in Şanlıurfa. Mothers and infants with chronic health problems were not included in the study. Human milk samples were taken at three different times; on enrollment (Day 6–10, visit 1), between 4 and 6 weeks postpartum (visit 2), and between 14 and 19 weeks postpartum (visit 3). Mycotoxin levels in human milk were measured utilizing Helica brand commercial kit. Results: Nineteen voluntary mothers and their breastfed infants with three human milk samples completed the study. The mean ages of mothers and infant (± SD) were 27.4 (± 5.4) years and 7.6 (± 0.9) days on enrollment. Median levels of ZEN and DON in human milk samples were 0.39 and 16.7 ng/mL, respectively. None of the cases had a ZEN daily intake higher than 250 ng/kg bw per day. However, three fourth of the cases had DON intake higher than > 1000 ng/kg bw per day. When adjusted for infant weight for age and sex, both ZEN levels and daily intake were decreased progressively from visit 1 to visit 3 (p < 0.001). DON levels and daily intake at visit 2 were found to be significantly lower in samples of visit 3 than that taken in visit 2 (p = 0.004 and p < 0.001, respectively). Conclusions: Breast milk monitoring study revealed that ZEN and DON mycotoxins were present in the mother-infant environment. Contamination levels changed during the lactation period.