Background: Malaria can significantly affect the structure and function of the placenta, leading to changes in its thickness and morphology, which maybe common low resources income countries such as Nigeria. This study was designed to assess the impact of malaria on placental thickness and morphology in the second and third trimesters of pregnancy in Onitsha Anambra state, Nigeria. Materials and Methods: The study design was a case control carried among pregnant women with malaria and comparing with apparently health controls. Both groups undergo laboratory test for malaria and ultrasound scan for placental thickness and placental morphology using standard protocols. Descriptive and inferential statistical tools were used for statistical analysis with level of statistical significance set at p < 0.05. Results: Malaria status did not have a significant effect on placental thickness (F(1, 394) = 0.041, p = 0.84). There was a significant main effect of trimester (F(1, 394) = 9.233, p=0.001). There is no significant difference in placental morphology between malaria-affected pregnancies and healthy controls (F(1, 396) = 1.049, p = 0.31). Conclusion: Placental thickness differs between the second and third trimesters and increases from the second to the third trimester in both malaria-positive and healthy control groups. Malaria status did not meaningfully alter the pattern of placental growth across trimesters. There is no significant difference in placental morphology between malaria-affected pregnancies and healthy controls and placental morphology does not significantly differ between the second and third trimesters. Also, the interaction between malaria status and trimester was not statistically significant.