The purposes of this study are  to determine: (1) Student’s representationof represent sequence of numbers based Bruner’s representation (2) Activity ofstudent’s abstraction in represent sequence of numbers based Bruner’srepresentation. This study uses qualitative descriptive method. The study is conducted inSMP Muhammadiyah 2 Surakarta on the VIIIA. Data in this study is obtainedfrom the results of tests based on student interviews. Subjects are taken withpurposive sampling technique  as much as 8 students. Data analysis is donethrough reviewing all data, reducing data, collating data in units, and checking thevalidity of the data. Data validation is done by triangulation of time. Data aboutstudent’s representation and Activity of student’s abstraction in representsequence of numbers based Bruner’s representation is conducted by interviewbasedtest.Students’answersareanalyzedtostudent’srepresentationandActivityofstudent’s abstraction in represent sequence of numbers based Bruner’srepresentation.   The analysis of data results: (a) Group I consists of subject WS, HA, DR,and AT. Subject in this group is achieve symbolic representation but they can’tmake a generalization. (b) Group II consists of subject EN and HN have achievedsymbolic representation and make a generalization. (c) Group III consists ofsubject IQ and RO that in enactive representation. Activities of student’sabstraction that represent sequence of numbers  are (a) Identification the problem(b) Find the conclusion from every case (c) Identify the  sequence of numbersbased with picture (d) Find the conclusion through imagine from the picture and viii  that experiment (e) Make a picture, flowchart or list name from the problem thatgiven. (f) Find a relation from its conclusion (g) Make a hypothesa (h) Write thesequence of numbers (i)  Applicate the sequence of numbers to solve the problem(j) Calculate the problems (k) Make a relation from every representation (l)Generalize