The purpose of this study is to build up mathematical models to age specific marital fertility rates(ASMFRs) and forward cumulative ASMFRs of Bangladesh. For this, the secondary data of ASMFRs havebeen taken from Bangladesh Demographic and Health Survey (BDHS). It is observed that ASMFRs followsquadratic polynomial model in 1996 and one degree polynomial model i. e. simple linear regression model in1999-2000. On the other hand, forward cumulative ASMFRs follow cubic polynomial models in both cases.Model validation technique, cross-validity prediction power (CVPP), , has been applied to these mathematicalmodels to check the validity of the models.