In this paper, a modifed TE$_{113}$/TM$_{012}$ triple-mode bandpass filter is implemented by using a modified inter-cavity iris in which the number of slots are reduced upto 50%. In a coventioanl iris two prirs of slot apertures are used to independently couple three resonant modes between two adjacent cavities. However, if transverse magnetic polarizability of a pair of veritcal slot apertures is used to control weak horizontal TE$_{h}$-TE$_{h}$ mode coupling, the width of novel iris slots would substitute for the slot length of the conventional iris, causing to eliminate the horizontal slot apertures. The measured data of two filters, which are the modified filter and ocnventional one, are compared. Experimental result shows that the characteristics of the novel triple-mode filter matches well that of the conventional filter.