Low-power　complementary　organic　circuits　need　to　combine　p-channel　organic　field-effect　transistors　(OFETs)　and　n-channel　OFETs,　which　are　based　on　p-type　and　n-type　organic　semiconductors,　respectively.　Unfortunately,　the　performance　of　n-type　organic　semiconductors　still　lags　behind　that　of　p-type　organic　semiconductors.　In　this　work,　the　performance　of　solution-processed　n-type　OFETs　was　improved　via　a　facile　effective　route,　by　blending　a　p-type　organic　semiconductor　into　the　n-type　polymer　semiconductor.　The　effect　of　the　p-type　organic　semiconductor　additive　on　the　morphology　and　charge　transport　was　systematically　investigated.　It　showed　that　the　mobility,　on/off　ratio　and　stability　of　the　n-type　OFETs　were　significantly　improved　with　incorporation　of　the　p-type　semiconductor.　The　p-type　organic　semiconductor　functioned　as　a　trap　center　for　minority　holes　and　decreased　the　trap　density　of　the　dielectric　surface,　resulting　in　an　enhancement　of　the　OFET　performance.　Moreover,　blending　with　an　appropriate　amount　of　p-type　organic　semiconductor　also　benefited　to　reset　polymer　semiconductors　stacking　order　into　the　direction　that　promoted　charge　transport.　However,　excess　p-type　semiconductor　addition　deteriorated　the　n-channel　characteristics　due　to　the　formation　of　a　percolation　network,　providing　a　pathway　for　hole　transport.　To　the　best　of　our　knowledge,　this　is　the　first　report　about　improving　the　performance　of　n-type　polymer　transistors　by　simply　blending　with　a　p-type　organic　semiconductor.　©　The　Royal　Society　of　Chemistry.