Chirally regulated pi-conjugated polymers containing platinum (Pt) complex moieties have great potential as chiroptically functional materials. In this study, novel platinum-containing conjugated polymers, poly(1a-2) and poly( 1b-2), were synthesized by the dehydrochlorination coupling polymerization of dichloro(4,4'-tertbutyl-2,2'-bipyridyl)platinum (1a) and dichloro(4,4'-dinonyl-2,2'bipyridyl)platinum (lb) with N-[ 3,5-bis(4-ethynylphenylethynyl)benzoyl] -L-alanine dodecylamide (2), and their chiral secondary structures in solutions were investigated. Poly(1a-2) exhibited bisignate circular dichroism (CD) signals assignable to the main chain chromophore (300-450 nm) in dimethylformamide (DMF)/MeOH = SO/SO (v/v). The presence of particles of Z-average = 30 nm was confirmed in this solution. These results indicated that poly (1a-2) formed chirally regulated aggregates. Single-crystal X-ray analysis of the model compound and density functional theory (DFT) calculations were carried out to examine the mode of aggregation of the polymers.