The experiment was conducted at the Tajpur village of the Lakshmansree Union, Sunamganj Sadar Upazila and Rahimapur village of the Beheli union, Jamalgonj Upazila, Sunamganj district during November 2016 to May 2017 to see the effect of variety and MoP fertilizer on the growth of boro rice varieties in haor areas. Two varieties (BRRI dhan29 and BRRI dhan58) and six MoP fertilizer rates including 147, 137, 127 [BARC Fertilizer Recommendation Guide], 117, 107 and 82 kg ha-1 [Farmers’ practice dose (FP)]. Urea-TSP-CaS04-ZnS04 application followed as BARC Recommendation dose of 300-112-75-11 kg ha-1 Farmers’ practice (FP) where 165 and 82 kg ha-1 Urea and TSP were used. The experiment was laid out in a randomized complete block design (RCBD) with three replications. Plant height of BRRI dhan58 (95.33 cm) was significantly higher than BRRI dhan29 (91.52 cm). Plant height also affected due to application of MoP fertilizer treatments at all stages of growth. Interaction effect of variety and MoP fertilizer showed significant variation at 45, 60 and 75 days after transplanting (DAT). At 75 days after transplanting (DAT), the higher number of tillers hill-1 (21.83) was produced by BRRI dhan29. But it was higher in BRRI dhan58 (14.20) at harvest. Higher number of effective tillers hill-1 (12.48) was produced by BRRI dhan58. The correlation values indicated that growth and yield parameters were positively significant except few non-yielding characters.