This paper presents a fusion design approach of multiport (1-to- $N$ ) in-phase/antiphase power dividing network with a bandpass response, which can be applied in constructing either the balanced or single-ended filtering power divider. The relationships of external $Q$ -factors ( $Q_{e}\text{s}$ ) between the in-phase/antiphase ports are constructed, and it is found that their $Q_{e}$ ratio is determined by power allocation regardless of the phase difference. Meanwhile, the two functions of power allocation and bandpass response can be designed independently. Based on the theoretical analysis, two kinds of filtering power dividers using the dielectric resonator (DR) are proposed. One is balanced and the other is single ended. Both of them can be easily built by properly adding feeding probes for the DR without increasing the circuit size, while the phase difference between the ports can be adjusted to be either in-phase or antiphase by altering the direction of the feeding probes. To verify the proposed design concept, the filtering power dividers mentioned earlier are simulated. Some of them are implemented and measured, and their measured results match well with the simulated data, showing good performance, such as low loss and good selectivity.