This　paper　presents　a　non-uniform　and　part-searching-area　algebraic　codebook　based　on　Algebraic　Code　Excited　Linear　Prediction　(ACELP)　speech　coding　algorithm.　The　non-uniform　algebraic　codebook　is　determined　by　the　non-uniform　statistical　properties　of　the　algebraic　codebook,　and　the　part-searching-area　is　determined　by　the　periodicity　of　the　algebraic　codebook　excitation　vector,　which　makes　up　the　insufficient　numbers　of　signed　pulses　in　algebraic　codebook　at　low　bit　rate.　In　order　to　preserve　the　continuity　of　pitch,　different　pitch　detection　methods　are　employed　for　speech/silence　frame　when　these　two　techniques　are　used.　Subjective　and　objective　test　results　indicate　that　the　reconstructed　speech　quality　of　4　kb/s　DP-CELP　speech　coder　is　improved　based　on　these　techniques,　especially　for　the　female　speakers.